Better Signal with Wall Wart Tamer?

[cruizer]

Hello,
The FM Transmitter is something I have always had a problem with. I can never seem to get a strong signal going out.
When I had the modded Belkin Tunecast to my now Vastelec FM (01 or 02, honestly can't remember which one I bought, and it doesn't say) Transmitter.

I had straight antenna's a di-pole, and now I am running (courtesy of my friends dad) a ground plane antenna.

So my setup. Vatelec FM(01 or 02) Transmitter powered by a wall wart, 30' of unspliced Mini8 coax (which is exactly what the guy at the electronics store told me to run), and a ground plane antenna onthe peak of my roof. And I still only get about 200-300'. The people at the other end of my block can't get a signal.

The signal is pretty clear directly in front of the house, but once you head away it goes downhill pretty fast. Will a Wall Wart Tamer help increase signal strength?

Thanks!
Brent

[LabRat]

FM01 - 1 piece FM02 - 2 pieces connected with a cable.

You should include some details on how you are powering your transmitter. I have an FM01, powered from a WalWart, with a ferrite bead on the line.
Quality and Range seems to be better than you described. I have since moved my antenna to a horizontal position, 1 ft off the ground. This has reduced
the range to "on the block".

[cruizer]

Thanks, therefore I have an FM02!
I am powering my FM02 with a walwart, sorry, thought I mentioned that.

[cruizer]

Well, last night I put 2 ferrite beads on my power wire, and noticed no difference. Like I said, the sound quality is very good, it just only goes a very short distance.

So Wall Wart Tamer, will it help?

[LabRat]

Based on your descriptions.. I don't think it would. I'm not a radio expert though, and so bow to the advice of others here.

[Mactayl]

Based on your descriptions.. I don't think it would. I'm not a radio expert though, and so bow to the advice of others here.

This is correct the Wall Wart Tamer will do nothing for your distance, it mostly used to clean up audio hum. Sounds like you may have a coax cable problem or antenna problem.

[RFBurns]

Power supply input voltage can affect range if the transmitter's final/s are not powered through an on-board voltage regulator..ie running straight off the B+ input being fed into it.

However if the voltage is too low or cannot deliver enough current, even with on board voltage regulators, the range can be severely affected along with the rest of the transmitter not operating at its proper operating voltage supply.

Most common range problems are directly related to the antenna, its tuning and feed line being used. Certain antennas such as the J-Pole or dipole require a matching transformer, or balum to properly take the feed line impedance and match it up to the antenna impedance. If this is not done, some of your signal will travel down the ground conductor of your feed line and right into your audio equipment on the ground path! This will also cause RF interference into your audio chain as well as embed RF on any other ground path in close proximity.

It is not easy to properly tune up any antenna with very low power RF being injected into them. It requires a very sensitive VSWR meter that can read in the mW ranges. The next best method is to use a receiver that has a signal strength meter and try to tune the antenna for the most signal indication on that meter.

There are schematics all over the web to build a feed-through meter that can measure the mW ranges along with measuring VSWR at these very low power levels. Build one and then calibrate it to a dummy load, then connect to your antenna and see where things are.

Happy Holidays!!

RFB

[cruizer]

Mactayl,
My coax, like I said is Mini8, which the guy at the electronics store (the owner) told me would be the best for my application. It's 30' long, and he put the connectors on it, since I don't have the proper tools. THe antenna is a ground plane that was given to me by my friends dad.

RFBurns,
First I am going to check the out of my walwart. I know it says 12v 50/60hz 600mA.

What kind of receiver would have a signal strength meter? I'm not familiar with those. But I am going to look into the VSWR meter. I had used an SWR meter when I was younger for my car CB, lol.

Thanks for the info!

[IdunBenhad]

Hi:
I'm not sure what you mean by "mini-coax". If it is the very small coal, approximately 1/8" diameter or so, then it is very high loss, even with only 30 feet. If it is RG58 or RG59, or possibly RG8X, then you have good coax.

Are you sure the antenna is made for the FM band? If it is not, then there is the problem or at least part of it.

It is very easy to make a simple dipole, as has been shown in several places, that works well. Take at look at dirknerkles dipole, which is a little sophisticated but works very well. Also look into the simple dipole in the thread "FM02 Transmitter Setup".

Also, check for shorts on the coax connectors using your ohmmeter, but be sure and disconnect it from the FM02 when you do. If you are using a ground plane, there should be no shorts on the coax. There will be no shorts on a dipole, either.

I hate to disagree with RFBurns, but I don't think you need to go to the expense of a VSWR meter. I made the simple dipole, hooked up the transmitter and got over 1/4 to 1/2 mile range with it hanging in a door held up with a thumbtack. It is now mounted horizontally in my work shed, tacked up to the rafters, and it still gets 1/4 to 1/2 mile. I have never measured it with a VSWR meter, although I have 3 of them.

With a simple dipole or ground plane, baluns and matching transformers are not necessary, even though their use may make a better match for the transmitter. You would probably have to have instrumentation to see it.

The FM02 should be supplied with clean, 12.5 vdc power, even though it has been shown to operate down to 6 vdc, it is not recommended. The Wall Wart Tamer or the W3 filter boards will supply that power. The FM02 draws approximately 75 ma (.075 amp), so the 600 ma wall wart is more than adequate.

[cruizer]

I'm pretty sure he called it Mini 8, it's definitely thicker than 1/8 of an inch, and he said it would be better than RG58 at 30', I did explain to him how it was being used. There's only a short distance of it in the house, and I can't get any definitive info off of it, so tomorrow I'll look on the outside.

As for the antenna, the guy I got it from knows a lot more about electronics than I do. I explained what I was doing and he said he had an antenna for me.

I used a dipole antenna the last couple of years, and my distance was marginally worse than with this new antenna.

I've got to fix a couple of my relay boxes tonight, I'll more into the Transmitter tomorrow.

[RFBurns]

Mactayl,
RFBurns,
First I am going to check the out of my walwart. I know it says 12v 50/60hz 600mA.
What kind of receiver would have a signal strength meter? I'm not familiar with those. But I am going to look into the VSWR meter. I had used an SWR meter when I was younger for my car CB, lol.
Thanks for the info!

Ahh the good ol days. At one time almost every hi-end home stereo receiver sported a signal strength meter, and even some "boom boxes" had them. These days all that can be found on home stereo receivers are digital displays of the frequency being tuned, perhaps a bar graph showing audio levels or EQ adjustment levels, but I have yet to see a modern home stereo receiver with a signal strength meter.

You can however find shortwave radios with the signal strength meter that can tune the FM broadcast band and use that to help tune things up.

@IdunBenhad: Actually a VSWR meter for the mW range is quite inexpensive and extremely simple to build from junk parts. I mentioned it here so that it gives everyone another viable option to peak their systems for maximum signal coverage and operational efficiency...not to mention help prevent issues on the antenna system that can burn up the finals.

At VHF frequencies, antenna problems crop up all the time. A slight connection issue such as corrosion or even dust can throw off an antenna's resonance by quite a bit, thus cause increases in VSWR or spiking of the VSWR. Basically running an FM setup without a way to monitor your transmission system is like flying a YF-22 at mach speed blindfolded. Although having a VSWR meter isn't an absolute necessity, it is akin to having a VU meter on your audio console to see where your levels are. Without a VU meter, there is no accurate way to know if your levels are good or not except with hearing over driven audio and distortions. Since we cannot "see" or "hear" RF energy emitting off a radiating element, there needs to be a way to know whats going on in the transmission system.

Here is an example. Typical setup, all working great. Then suddenly the signal range reduces or gradually reduces. Everything "looks" ok with the antenna and coax..but for some strange reason the signal is not going out as far as it did at the beginning. How is one to know there is a problem on the antenna or coax if there is no way to measure it to see if there is a problem...like possibly moisture got into the coax fitting and corroded the center conductor inside the coax...and the moisture traveled down the inside of the coax, ruining it. It "looks' ok on the outside because the outer jacket looks ok, but that does not tell us if there is a problem inside the coax, a fitting or if the coax has changed impedance due to corrosion or flaky connections in the fittings. A VSWR meter will tell you two things to find the problem. Put a dummy load on the tail end of the coax and that will tell if the coax is at fault, or put the VSWR meter and transmitter right at the antenna to check for antenna problems.

Perhaps it is just the broadcast engineer coming forth in me. I tend to dive into things full force and never overlook anything. Then add the electronic and electrical engineer aspects and we go to town..party time! ;)

But the point I was trying to make is that even at the mW ranges, any issues on the antenna system or transmission line, especially at the mW ranges can drastically reduce your signal range down to practically nothing. A VSWR meter is a sure fire way to tell you if there is indeed a problem with the antenna system or feed line. Without one, its all guessing and shots in the dark...blindfolded as it were. After a while, all the guess work ends up in frustration..like constantly walking into a brick wall because your blindfolded and cannot see which way to go to stop walking into that wall.

Just providing some additional info for everyone to help out. :)

Happy Holidays!!

RFB

[dirknerkle]

RFBURNS ---

You said a VSWR meter would be easy to make? This would be a perfect time for you to make a HOW-TO! Share the info with everyone else -- sounds like it could significantly help folks.

There's a HOW-TO forum that is a perfect place for such a gizmo!!! OR even better, write it up as a Wiki article!!!

[RFBurns]

RFBURNS ---

You said a VSWR meter would be easy to make? This would be a perfect time for you to make a HOW-TO! Share the info with everyone else -- sounds like it could significantly help folks.

There's a HOW-TO forum that is a perfect place for such a gizmo!!! OR even better, write it up as a Wiki article!!!

I will consider that. I do have a few of my own designs of VSWR meters. Two of them use the analog meter and one has LED bar graphs, which the LED bar graph meter is more sensitive and works very well for the mW ranges, and is a bit more accurate tracking both VSWR and forward power.

Some CB VSWR meters will work quite well for this purpose. One I know of is a Workman SWR 3P. It has the standard analog meters and uses SO 239 connectors. It also has an on-board field strength function which comes in handy measuring field strengths across a wide range of frequencies. Though not accurate or sensitive as a Potomac FIM that the FCC field agents use, it can aid in either troubleshooting or setting up a system for the first time, plus have a way to constantly monitor the transmission system.

Happy Holidays!!

RFB

[cruizer]

Just checked the voltage going into the unit, it's a steady 12.05v.

[IdunBenhad]

Hi:
Cruizer: That's an acceptable voltage for the FM02. Keep checking for shorts, etc. That may be where your problem is.

RFB, I don't argue the value of an SWR bridge or other instrumentation. If fact, I think it's great if one has access to such equipment. I too, have worked in the communications end of it almost all my working life, as well computers when the only way to have a computer was to design and build it yourself. We did, that is, friends and I. If fact, I left some of my instruments with the State of Colorado when I retired. Wish I had it back!

Ah yes, the days of Bird Wattmeters and MW meters. I had one that went up to 100 MW. Sure would be useful now!

Anyway, my point was that it is possible to exist without instrumentation if one uses their head and try to reason out the problems. It does sound like Cruizer could use an SWR bridge. It just might help solve his problems.

As many on this forum know, I'm "El Cheapo Numero Uno" and try to get by as simply as possible, so do not think I undervalue instrumentation or am zinging you, because that is not the case.

I would be most interested in seeing a how-to on a MW SWR bridge. I will probably be one of the first to build it. That is, after I get my display up and running! I am 5 days late and counting in getting everything running.

[RFBurns]

When I get some time I will write up a "how to" for a simple but effective VSWR meter for the milliwatt power range. It can be built using salvaged and junk parts or parts purchased new.

Once ready I will post a link here to a PDF for everyone to download. :)

Happy Holidays!!

RFB

[dirknerkle]

I think that a lot of times, all of us overlook the most commonly simple things and immediately delve into the exceedingly technical minutiae involved to make things professionally perfect. We generally tend to over-engineer a lot of the things we do in this hobby, and in some cases it's probably warranted but in others, it's just spinning your wheels.

For example, does it matter whether your antenna cable is 10 feet long or 15 feet? Or whether your antenna is perfectly tuned for 88.1mhz but you have to use 88.3? Geez, c'mon.... get a grip! More often that not, with these little FM transmitters, you'll find that just hanging a 6' wire out the window will probably work just fine. There are thousands of college kids who've proven that from their dormitory windows.

But there are some things where taking a measured approach is a pretty good idea, or at least applying common-sense, simple methods to your projects.

Simple methods such as using your DVM or VOM to check the continuity of the antenna cable as well as for a short between the core and the shielding will immediately identify whether you have a cabling or connector problem.

Checking the antenna itself for shorts is a slam-dunk. So is checking voltage of the power supply.

But amazingly, most of us are so anxious to fire it up and see how it works, we often skip these simple, cautionary and protective steps.

Do the due-diligence first. And nomatter how many cat-5 cables you've ever made, always, always, always check it with a continuity tester of some kind before you use it. Always, always, always check a power cable that you make for shorts BEFORE you plug it into 120vac.

It only takes a minute and can save you sooooooooo much agony down the road. And above all, learn to recognize the difference between over-engineering a situation and applying common analytical methods first.

[lightman]

Is that a liquid or bar soap box? LOL.

Agreed. I use a Cat5 cable tester from Home Depot to eliminate headaches. I also test my home brew extension cables on the bench before using in my set up. I make too many mistakes on my own (ha ha) and need all the help I can get.

Now...I got to wash my hands...where did I put that soap....

[cruizer]

How would I go about checking my coax for shorts? Keep in mind I did not go to school for this kind of stuff, hence all the questions, lol.

Thanks again for all your help!

[dirknerkle]

How would I go about checking my coax for shorts? Keep in mind I did not go to school for this kind of stuff, hence all the questions, lol.

Thanks again for all your help!

Here's where some basic understanding of electricity is really important, because it's hard to have a lot of respect for something that can actually kill you if you aren't paying attention. All folks new to this hobby should have a basic understanding of how electricity works because we often deal with very *dangerous* electricity. Because you asked, I'll type a few things, but really, go to HD or Lowes or on-line and do some reading on the topic. It could save your life or the lives of others.

Electrons flow through wire only when they have a way to return. Without the return path, they can't go anywhere. You turn on a wall switch and the only reason the light goes on is because the switch allows the electrons a path to flow from the power source to the light, through it, out the other side and back to the power source. In other words, this is called a "complete circuit." When the switch is "off" it's called an "open" circuit because there's a break in the path.

Look at the end of a piece of coax. You see the center core wire, and you'll see that it's surrounded by some type of insulating material, and on the outside of that is some sort of metal shielding, possibly some stranded wire and/or something that resembles tinfoil. The insulation keeps the two of them from touching one another.

When the circuit is "completed" there is no resistance (well, very little anyway) for electrons to go out and come back. When you measure a completed circuit with a DVM or VOM, you should get a value of zero or at least something extremely close to zero. When you measure an "open" circuit, you generally won't get much or any reading at all because there's no way for the electrons to go out and come back. Is this starting to make a little sense???

If your coax has a short in it, it means that the center wire and the outer wire have come in contact with one another. Measuring with a DVM or VOM will give you a zero (or near zero) reading because the electrons can go out one wire and come back on the other. It's a completed circuit. You should always measure this before you connect it to anything so that no OTHER pieces of hardware can influence the DVM reading. In almost every case, a completed circuit is NOT what you want with almost any kind of wire. If you measure the wire and you get no reading, then the core wire and the outer wire are not touching. That's good news.

Then check the antenna. The same thing should happen -- you do NOT want to see a reading of zero. This may be confusing because you might wonder how an antenna works. Well, the electrons have to go someplace for it to work and they actually do -- they pile up on the antenna and create an electromagnetic force which goes out into the atmosphere as your radio signal. Radio frequency energy is slightly different than electricity that courses through a lightbulb, but the point is that if the antenna has a short or the coax cable has a short, the electrons never get to the antenna -- they go back to the power source instead, which results in no output out the antenna.

This is more than enough for now, but it should give you at least a little understanding of how to check for shorts and why they are generally not a desired thing as it comes to electricity.

But you should also understand that in some cases, a short can also be a GOOD thing, too. For example, if you deliberately connect the core wire to the outer wire of your coax, you would expect to get a near-zero reading on your DVM or VOM on the other end. But if you DON'T get a zero reading, it means that the wire is broken somewhere inside the casing. That would indicate a bad wire that should be replaced.

[LabRat]

Just going to try and decode some of Dirk's TLA (Three Letter Acronyms)

DVM = Digital Volt meter
VOM = Volt/Ohm Meter
VHF = Very High Frequency

The LFLA (Longer Four Letter Acronym)

VSWR - Voltage Standing Wave Ratio

The SA (Short Acronym)
FM = Frequency Modulation

and the LAIP (Last Acronym In Post)
(this was a tough one... I'm going with...)
RFB = "Read-the eFFin Book" :w00t:

[ErnieHorning]

Something else to note… We often use the word ‘short’ but a lot of times in a low current circuit (i.e. antenna); it doesn’t have to be zero ohms. You could get water in somewhere and have a resistance of greater than 100K. It’s not a short but it will still provide a path for current. Your transmitter will still work but all of the output won’t go to the antenna. If the transmitter is good and the antenna is good and you’re still not going as far as everyone else, then look elsewhere for the problem.

The cable and antenna should look like an open to a DC ohmmeter. Set it to the highest range if it’s not an auto ranging meter.

[cruizer]

My neighbor came over and helped me out today, he works at a home electronics store, apparently knows a little about antennas.

I found out from him that my antenna had a load coil on it. So we found the length of the load coil, and adjusted the length of the antenna with the load coil for 1/2 wave instead of 1/4. We checked the resistance of the coax and it was perfect. We checked the resistance of the antenna, perfect.

We increased seemed to increase the reception to about a 1/4 mile, but now we have some static.

Any idea why it would be staticy?

[IdunBenhad]

Hi:
Is the static with or without audio. You should check with the audio disconnected from the transmitter.

If your static is caused with the audio connected, then you are probably overdriving the transmitter. You should cut the audio down to a low level.

I'm not sure what kind of antenna you have, but if it is a groundplane cut for the FM band, then it should not have a loading coil and the radiating element should be 1/4 wavelength (about 31.68 inches) with 3 or more radials approximately the same length. It sounds like you may have a CB antenna and that is not resonant in the FM band. CB is around 27 Mhz and FM is 88 to 108 Mhz.

If this is the case, you can harm your transmitter if the antenna is not accepting the power properly and sending it back toward the transmitter.

Please Google up a groundplane antenna to see what it looks like. Also, do the same for a dipole antenna. You are having far too many problems with the antenna for it to be a correct one for the FM band.

[RFBurns]

If using a loaded CB whip antenna, removing the loading coil will vastly improve a lot of things!

Happy Holidays!!

RFB

[cruizer]

We did not remove the audio cable, but we did pause the music player, and the static was still there.

The computers audio is approx 33%, which is where we found the best sound quality to be while testing. I remember reading somewhere it needs to be less than 50, so I've always kept it at that or lower.

The ground plane has 8 radials, all the same length. We had removed them, but it made transmission much worse, so we out them back on. The

We looked up the specs for this antenna, as the name and model is written on the antenna itself, and it said it can be used as a transmitting antenna in the frequency range we're working in.

Here is the spec page:
http://www.ges.fr/PDF/D-130.pdf

[IdunBenhad]

Hi:
Sorry to rain on your parade, but that antenna is not intended as a wide band transmitting antenna. Even though it is listed as "wide band", it is built for receiving.

Look at paragraph #5. It lists several frequencies that the antenna can transmit on, none of which are close to the FM band. For instance, 6m is 50 mhz; 2m is 144 mhz; 70cm is 440 mhz. The FM band is 88-108 mhz.

RFBurns is right. You may be able to salvage the antenna by removing the loading coil and replacing it with a rod about 28.8 inches long. Leave the radials but remove the disc elements. And if possible, shorten the feedline. By the way, they gave a specific length for the feedline. That may be part of the antenna when it is used as it was designed for, but the length should make no difference if you convert the antenna to a groundplane

The only thing I can say about the static is that you are receiving a weak signal and static or noise will increase as you get farther away from the antenna. The whole problem may be as said before. You don't have a proper antenna.

Look at this to calculate the vertical element: http://www.csgnetwork.com/antennagpcalc.html. The length of the radials as shown on the data sheet is probably OK.

You may be able to put a jumper across the loading coil. This then becomes part of the length of the vertical element. As the length is not shown in the diagram, this may have to be shortened or lengthened to get the 28.8 inches. In any event, the vertical rod needs to be approx. 28.8 inches.

[RFBurns]

I also wonder about the angle of those ground radials and the discone section working correctly with the vertical when the loading coil is removed. I also noticed in the antenna's specifications that it is not designed for transmitting in the FM broadcast band. Removing the loading coil and replacing with a solid vertical element could bring it into the FM band range, but I suspect there may be some experimenting required with the vertical element length to get it to work effectively.

Happy Holidays!!

RFB

[cruizer]

Welp, none of that seems to be good news. We wanted to not use the loading coil initially, mainly because we didn't know it's length. But we could not find a fitting to get the whip attached to the antenna without it. We tried to change the angle of the radials, and the reception got worse. We removed the radials, and the reception got worse. We removed the discone, and the reception got worse. But those tests were done with the loading coil on it.

An no, the static/noise does not increase as you get father away from the antenna. In fact the signal stay pretty much constant for about half a mile, then it's an almost instantaneous drop off.

IdunBenHad, I want to make sure I am understanding you correctly. Are you saying to basically replace the coil with a length that's 28.8 inches and then add the 31.68 inches for the 1/4 wave on top of that?

[IdunBenhad]

Hi;
No. The total length of the vertical rod or element should be 28.8 inches. This is 1/4 wavelength according to the calculator I mentioned in post #27.

IF you can short the loading coil with a length of wire mounted on the outside of the loading coil shield, measure that and add enough rod above the coil to total 28.8 inches.

The radials can be shortened to the length shown in the calculator, but for this purpose it is probably not necessary. The radials as shown in the diagram are a bit too long, but not much. The radial length is usually not critical.

Look up a ground plane to see how it is constructed. You will see it is pretty close to what you have in the antenna now. There is the possibility of being able to insert a small diameter rod into the center conductor opening that the loading coil plugs into, but this would probably not be too substantial.

Also, check to see if a PL259 connector will screw onto the loading coil mount. If so, you can solder the rod into the center connection in the connector and screw it on. A PL259 is the same connector that is on the coax that plugs into the antenna at the bottom.

[cruizer]

OK, when I use the calculator for 90.9, it come to 30.89, so what I am I doing wrong? (31.68 was for something different, got them mixed up.)

As for the PL259, the load coil go onto a threaded rod. The PL259 is totally different.

[IdunBenhad]

Hi:
Nothing wrong. When you plug in your 90.9 frequency, it calculates the length.

Try entering 88.5. You will see that it has a longer length. Enter 107.5 and you will have a shorter length.

The length of the rod varies with frequency.

That is probably a 3/8-24 thread. Try removing the outside can from the loading coil, if you can. I wouldn't destroy it, but try to get it off. You can then remove the loading coil and put a direct wire across it. You now have a mount for the rod.

[cruizer]

I will give that a shot, thanks!

[jboyles7]

The range you are getting is really short, so I agree with Dirk: Are the fundementals met? Is there a short in the ANT lead or something? Can you put a simple test ant on it, without the cable and get better range? I'm in no way the RF expert, but given the very short distance, shouldn't we step through the basics?

[cruizer]

jboyles,
1/2 mile is a short range for the FM02? I thought that was about what every one else was getting?

IdunBenHad,
I just want to clarify, is the total distance going to include the loading coil with the direct wire, or just the rod that is attached to it?

[jboyles7]

I must be reading somthing wrong. I thought you were only getting 200'? OOPS -- I missed a post.

[RFBurns]

If the transmitter is working correctly, everyone should be getting at least 200 feet plus just from using a simple whip or a short piece of wire connected to the center pin of the SMA RF output connector.

The external 1/2 wave or ground plane through 25 feet of coax should give a couple of blocks at least.

The external 1/2 wave dipoles being used are simple and not much can go wrong with them next to typical connection issues like corrosion or loose or weak/broken soldering.

I mentioned this before, but this FM02 not only has no low pass filter, but no protection against static charge buildup, which WILL happen on those open ended dipoles. Chances are..everyone experiencing this drastic reduction of range with the outdoor antennas, and even still with the "test whip" or piece of wire and cant get 5 feet..well that is s sure fire indication that the final (Q401) is shot...probably zapped by static charges.

There will be just barely enough RF signal coming out of the FM chip itself to pass through the defective output transistor to pick it up close by the transmitter. One way to test if that RF output transistor is shot is to attach a signal booster amplifier to the output of the transmitter. These were commonly used as antenna amplifiers for television and have F connections for both in and out. Plug one of these into the transmitter and to the antenna and I bet your going to get some range back.

That test should only be done on units suspected of a bad RF output transistor. If you attempt to connect one of those signal booster amps to a good working FM02 or other transmitter, it will most likely over-drive the booster amplifier and damage it, and possibly damage the good RF final too..so don't attempt it on a good working unit.

Using the signal booster amplifier will get you by for this season. Before next season, either some modifications are called for in the FM02 or complete TX replacement.

Antenna Booster (http://www.amazon.com/SIGNAL-BOOSTER-AMPLIFIER-ANTENNA-CABLE/dp/B003DRMKXW)

http://ecx.images-amazon.com/images/I/215cLG-3jhL._SL500_AA300_.jpg


Happy Holidays!!

RFB

[ErnieHorning]

An no, the static/noise does not increase as you get father away from the antenna. In fact the signal stay pretty much constant for about half a mile, then it's an almost instantaneous drop off.If you’re transmitting half a mile, it sounds like the antenna is working fine and you should be looking elsewhere. FCC only allows 200 feet anyway.


Is the static with or without audio. You should check with the audio disconnected from the transmitter.
We did not remove the audio cable, but we did pause the music player, and the static was still there.
Did you ever try just unplugging the audio cable, like was suggested? Just stopping the music doesn’t tell you if the problem is with the PC, it only tells you that it’s not in the audio file.

It’s kind of like changing the tires on a car because the engine is making noise but if you turn up the radio, it’s not as bad.

[cruizer]

jboyles7,
Originally I only got about 200', so you weren't wrong. But through testing, modification, etc, I have increased me range but decreased quality.

ErnieHorning,
No, I have not tried that yet. I understand your analogy. I assumed if signal wasn't being sent to the transmitter, it was the same as it being unplugged. I will test that tonight.

[IdunBenhad]

Hi:
WHOA---STOP----

See below. I got in too much of a hurry.

[IdunBenhad]

Hi:
WHOA--STOP---
This is getting ridiculous. All Cruizer wanted to know was how to get a better signal and clean up his audio. We have filled him up with all kinds of theory and how the FM02 is not designed properly and a hundred other things that at this point in time he has no interest in and should not be wasting his time on. If fact, he shouldn't be wasting his time on this entry.

All of this type discussion should be in a thread of its own. From my point of view, if the antenna has been modified and he is getting good range, then his next problem is getting rid of the static.

That's it! He doesn't care about low pass filters, amplifiers, antenna theory, etc. While all this information is interesting and is informative, we can save it for a later time.

So, having spouted off, I'm going back to my sequencing, I have no time for this right now except to help Cruizer get his signal cleaned up. We can discuss transmitters and theory later in another thread.

[Mactayl]

Hi:
WHOA--STOP---
This is getting ridiculous. All Cruizer wanted to know was how to get a better signal and clean up his audio. We have filled him up with all kinds of theory and how the FM02 is not designed properly and a hundred other things that at this point in time he has no interest in and should not be wasting his time on. If fact, he shouldn't be wasting his time on this entry.

All of this type discussion should be in a thread of its own. From my point of view, if the antenna has been modified and he is getting good range, then his next problem is getting rid of the static.

That's it! He doesn't care about low pass filters, amplifiers, antenna theory, etc. While all this information is interesting and is informative, we can save it for a later time.

So, having spouted off, I'm going back to my sequencing, I have no time for this right now except to help Cruizer get his signal cleaned up. We can discuss transmitters and theory later in another thread.


I pretty much summed up this in post #6 of this thread...and it has completely went off the deep end.


This is correct the Wall Wart Tamer will do nothing for your distance, it mostly used to clean up audio hum. Sounds like you may have a coax cable problem or antenna problem.

[RFBurns]

Well better to have enough information than not to have enough. Suppose it was a problem with your sequencing and you been through thick and thin trying to figure it out. Would you want as much info as possible to resolve the on-going problem?

I am surprised at this 2nd "B" rate prospective some are displaying to the audio portion of their display. No doubt no one is taking that "cheap" approach with any of that are they? So why should any of you take this cheap attitude towards the audio part then?

Your gonna get what you pay for...and if your not cutting corners on the display portion and all that is working great, but taking the cheap way out on the audio side and its not working quite alright, then perhaps prospective might want to take a different turn..as well as attitude...or don't use the audio part at all if your not going to at least do it half right.

Can't have it both ways. Otherwise the result is what is going on now...failures.

Happy Holidays.

RFB

[IdunBenhad]

Hi:


RFB
Your gonna get what you pay for...and if your not cutting corners on the display portion and all that is working great, but taking the cheap way out on the audio side and its not working quite alright, then perhaps prospective might want to take a different turn..as well as attitude...or don't use the audio part at all if your not going to at least do it half right.

RFB, that may be true, but the point of my comment was that he did not need all this discussion of theory, poor design, etc., he wanted a fix and wanted the fastest and easiest way to do it.

We have what we have and the focus of this forum is to get things done as easily and low cost as possible. The FM02 has proven to both a very versatile radio and at the same time has presented some problems because of its' minimal design, but hundreds of DIYCers have used it successfully and gotten their signal on the air.


RFB
I am surprised at this 2nd "B" rate prospective some are displaying to the audio portion of their display. No doubt no one is taking that "cheap" approach with any of that are they? So why should any of you take this cheap attitude towards the audio part then?

While many of us are well versed in theory and construction and have had lots of experience and have even worked in the field for many years, it is not our goal to dazzle them with BS, but to try to guide them through difficult problems with the least possible pain.

I appreciate and love to expound theory and how things "should be" and how to do it, but when someone is in trouble and wants a quick fix, then that is what he should get and we should leave the extended theory for another time and place.

I do not intend to get into any argument with you are any other member of DIYC. The above is my opinion and that is how I operate.

If you want to discuss theory, how-tos, etc, let me know. I'm ready at any time, even with a 2nd rate attitude.

[RFBurns]

Just trying to help with information not being covered.

And by 2nd rate attitudes I mean that the audio portion of the whole should not be put in the back seat in attention. It should be up in the front along side the attention level of that being given to the displays themselves.

Some of you are having no problems, while others are having repetitive problems that obviously all these simple fixes are not cutting it. So at some point you have to toss out the "simple" approach and start digging a bit deeper, regardless of how much one might like it or not, or how much one knows or does not know.

In other words...when the suggested fixes are not fixing, its time to try something else. That's all Im saying. What better than to get first hand advice from an actual RF engineer who can do this stuff blindfolded and both hands tied behind their back? Why go on guessing and fiddling and piddling around when right in front of you are sure fire troubleshooting tips and remedies from that experienced engineer who is asking nothing in return for their gracious gift of providing detailed technical advice when such advice is rarely given away.

Maybe that advice would be more appreciated if everyone knew how much a consultant would cost, even to resolve these "little" problems.

Now one person might "operate" in one way, but that does not mean that is applicable to everyone. If anyone finds my advice a bit over the edge...fine..keep it to yourself because there are some out here that just might have a different opinion than yours..so let them speak for themselves. Let them speak out for themselves that the advice is too difficult to understand, or too complex or too detailed.

I don't intend to get into a debate either. But if someone is asking a question on a public forum and I have an answer, you can bet I will provide that answer with no BS attached. It can be taken into consideration or not taken into consideration. But at the very least..let those who are asking the questions decide if the information is worthwhile to them or not.

I hope everyone has a great holiday and the displays put on a fine show. My contact info is in the profile, it is an open invitation to send questions and seek answers. I've done enough here...at least others think so...so the door is open to anyone who wishes to get another prospective on all these problems that apparently are still on-going that the simple and cheap are not resolving.

RFB

[cruizer]

Just to curb this, I love learning new stuff! So having extra information to me is just a bonus. While I didn't go to school for this stuff, I do have a technical background, which helps me understand things a little more.

That being said, I thank everyone for their input so far. Unfortunately I have not been able to test anything. When I get home from work, the show is already running, and when it's done, it's late, and cold and the roof is usually frosted over. So it'll probably be Saturday before I get back up there.

[ErnieHorning]

While this may be the most technical site of its kind on the internet, I believe that the majority of the members here are non- technical people. I spend my entire day time in an engineering environment and while this is a normal level of speech, I try to keep my posts here to a common street level that anyone can understand.

For most Engineers, good enough usually isn’t. There’s always a way to make something better no matter how subtle; it’s in our nature.

RFB, you’re definitely an extremely valuable resource to this site. What I would suggest is that you add a section to the Wiki for antenna design. Explain in a simple language that anyone can understand but also extend to a more technical ‘why’. This kind of information is easily lost in a thread as it gets older and people stop posting in it.

[ags0000]

For most Engineers, good enough usually isn’t. There’s always a way to make something better no matter how subtle; it’s in our nature.
I fall into that category. I don't want to change, either.


RFB, you’re definitely an extremely valuable resource to this site. What I would suggest is that you add a section to the Wiki for antenna design. Explain in a simple language that anyone can understand but also extend to a more technical ‘why’. This kind of information is easily lost in a thread as it gets older and people stop posting in it.
Great idea Ernie. +1 to that.

[cruizer]

OK, this is what I did this weekend. It was still quite cold, and there was snow on the roof, so I opted not to go up and mess with that antenna.
First, I removed the audio plug from the transmitter, still static.
I then built a dipole antenna, hooking it up with a short piece of RG58 cable, and by short we're talking about 5 feet. I put the antenna in my window. Still static.

So it must be the transmitter causing the static then? Any fix to this?

[ukewarrior]

When you say 'static' do you mean crackly sound in your audio?
By the way, have your tried more than one radio to receive your signal just to rule out the radio?

OK, this is what I did this weekend. It was still quite cold, and there was snow on the roof, so I opted not to go up and mess with that antenna.
First, I removed the audio plug from the transmitter, still static.
I then built a dipole antenna, hooking it up with a short piece of RG58 cable, and by short we're talking about 5 feet. I put the antenna in my window. Still static.

So it must be the transmitter causing the static then? Any fix to this?

[cruizer]

yes, like a crackly sound in the audio. On some of the songs, it's really affects the sound quality.

And yes, I have used one radio in the house, one in the garage, and the car and truck. All sound the same.

[ErnieHorning]

Or a different frequency.

[cruizer]

Tried different frequencies, they sound the same.

[ErnieHorning]

• Clean power
• No input
• Multiple frequencies

At this point, I’d have to conclude that it’s the transmitter.

The antenna would change the transmission range and could potentially change the way the audio sounded but it wouldn’t add noise to a dead carrier.

It’s probably a bad transistor or capacitor. It could be in the audio or oscillator section. Maybe worth messing with in the off season.

[cruizer]

Suck.

[ukewarrior]

I agree with Ernie.
Sounds like the transmitter.