RM AD 203 Stinger Board

[ThirstyBoots440]

Not bad on the install, but I'd be wary of the hot glue. If it's working for you then it's serving it's purpose. I've ran stinger boards in the past, both with the infamous RM3 transistor and one with a 1446 pill. While they're good for a few extra watts, I'm more of one to go with at least a 2 pill external. Either way, keep rockin that radio and keep us informed on how it holds up!

FWIW, I'd run another stinger before I run another RFX75 again, at least you have some control over the carrier with the stinger board, where the RFX unit can't handle much more than 12 watts carrier, the PEP ratings cause a lot of harmonics and over modulation...just my .02

 

[unit511]

Well I have been using this setup for about a week and is working nicely.... Still no meter. Can talk skip to midwest no problem but could not make it to west coast yet. Talking to my locals the aluminium heatsink does get warm.....but because it's on the outside of the case the heat is not an issue. I don't really care if it doesn't push out at rated wattage. I just wanted alittle extra when I need it. I need to unlock the clarifier on the 453 - next project! I was ragchewing with a local yesterday and a person that was born with a radio in there mouth was extremely rude to us. Why is it that cb'ers are so efin rude? I am the new guy here ......I am just talking with a new buddy.... you want the channel have it man there are plenty more. You see this radio is not that important to me. I have a life ....you are looking for one. I have learned from my childhood that people like you are just d-bags and will always be one. I would rather change channels or turn the radio off than to bother with your kind. Experience has taught me well. I repeat I am the new guy just looking to talk on the radio.....you have a problem with me talk to me like a gentleman...you will find I am a nice guy. Don't tell me to throw the radio in the garbage because my clarifier is locked and you have to keep moving the adjustment to hear the conversation. Don't listen or put the adjustment in the middle.... I will not get into a pissing match about a radio. Like I said I will shut off or change channels..... there are plenty of other decent people to talk with..

 

[unit511]

Follow up on AD 203 Install

Still works great. My radio however started to go" funny" on me. When I turn it on the audio would be so friggin loud it would hurt your ears and the volume control did nothing to reduce the volume. When I jiggle the band selector switch the volume would be controlled by the volume control. So I opened the radio again and resoldered all the board connections on the selector switch. Seemed to help for awhile but then the problem came back with a vengence...... I couldn't turn the radio on without the volume going way too high ...wife sleeping in next room god forbid I should wake her up...there would be hell to pay! So again I opened the radio and did further investigating. I had to remove the faceplate to get a good look at the situation. I hate taking them off....Well I did find the problem. There was too much play in the side to side motion of the band switch. I grasped the sides of the switch with a needlenose and applied good even pressure and brought the sides of the switch closer together. From years of use the tubular knob had created too much side play. Now the switch is alittle hard to change bands with but the volume control is now fully functional....Radio works great again. Highly recommend this board....

 

[skybolt58]

internal amp..

Get the SX-175 by magnum, you will like it much better, I put one in my 2950 and I get 200 out of it, you can switch it also. Nice amp! copper has had it for 109.00

 

[unit511]

Just playin' with some toys. Trying to get my hands wet. I am learning and having some fun,ya know? I am getting a 959 with mods very soon. A magnum will be one mod. 73's

 

[Tim Chambers]

The key to making any kind of "stinger board" work, is keeping the RF it generates out of the radio's circuits, shielding is fine, however it does not seem that anyone has made the leap of imagination to keep the power feeding the stinger board clean. someone said something about the stinger board hurting the power supply of the radio..... If you hooked up the power feed for the stinger board to the circuit board power, well, you deserve what you get. The power is supposed to be hooked up to the terminal inside the radio. I would attache the ground to the PCB ground.... Now for the most important thing, add at least 3 turns each, to two or three ferrite cores
(from a linear amplifier transformer, for instance) to the HOT + wire feeding the stinger board. THIS WILL ABSORB THE RF THAT LEAVES THE STINGER BOARD AND THEN ENTERS YOUR RADIOS CIRCUIT BOARD. Don't believe me? Try it! Remember, RF RUNS FROM GROUND and as such, RF exits any transmitter via it's power supply (of course it goes mainly out your antenna) Curing overly loud talk back, volume output, etc, can all be done by this simple and inexpressive method. Running an external amplifier and it produces feed back? Put some ferrites on the POWER 12V + WIRE, NOT the ground wire. Simple and effective. I'm not a HAM, however this is an old school HAM trick to get everything from motor noice from your wipers, to feedback under control.

 

[nomadradio]

A look inside a RCI2970 or similar radio will reveal how the factory keeps the linear's output power from leaking through the power wires back into the radio and causing headaches.

Chokes on the hot and ground lead to the amplifier board are important. And adding more filtering to the two wires feeding power from the power socket into the radio will usually be a good idea.

We got in the habit of using a "common mode" choke made from a 1-inch diameter toroid coil. Both hot and ground wire are wound onto the choke. The hot side on one half, the ground wire on the other, an equal number of turns on each side. The turns count isn't critical, and the size of the wire will impose a limit on this. Winding one of them clockwise and the other wire counterclockwise will allow the choke's core to cancel any RF leaking out of the amplifier's power input before it can reach the power socket. on the rear panel.

73

 

[Onelasttime]

In addition to the above once you cut the big resistor to get more power out of it the impedance mismatch is insane just as bad as the RFX series of amplifiers. So do not clip the big resistor! They are cheap and so long as you d not clip the big resistor and are happy swinging to about 50 watts rms they are fine. Cheap materials,components and dirty design. A steel heat sink with no fines and steel heat spreaders is about as bad as it get's. Keep it at 50 watts though and it does not matter and should last a long time if you keep your swr's low! I think they fine if set up cleanly and the above restrictions are kept in mind. If the radio is clean and properly aligned they will work just fine!

I am not a huge fan of mounting rf amps inside the radio. I am not a fan of not having a real heat sink with fins or forced air. I am also not a fan of non-rf specific fet's being used for rf service since they tend to have ZERO gain at automotive voltages in the 24-30Mhz we operate in. Cheap and trendy though!

Truthfully finding a single bjt hi power rf amp board would be a better option if such a thing is on the market? Something like a single 2sc2879 or 2290 would be more powerful, have more gain and would be much more durable!

 

[nomadradio]

And never underestimate the value of a metal shield around the amplifier. All factory-installed amplifiers have one.

For a reason.

73

 

[El Kabong]

Has anyone tried to put one of these amps in a Cobra 2000 and not cooked the radio's power supply?

 

[Shadetree Mechanic]

Has anyone tried to put one of these amps in a Cobra 2000 and not cooked the radio's power supply?

I would bet that the power supply in the radio can barely run the radio as it is. You would be better off with a separate amp and power supply.

 

[El Kabong]

The included 10 Amp fuse was a good clue. Rats!

 

[Tim Chambers]

I've had no issues with the AD 203 and I've been installing them for years. Currently replacing the 2 transistor PA in a Saturn Turbo. Seeing 123 pep currently, probably a bit more before it's all done. Just follow the directions and ensure the radio it is going into has a 1-2 watt dead key. Snip the largest resister on the stinger board as well. Add a few ferrite beads to the power wire to the stinger board, that helps a lot.

 

[smiley83]

Has anyone tried to put one of these amps in a Cobra 2000 and not cooked the radio's power supply?

I know this is a old post. I have one in my cobra 2000. All you have to do is run the power to the 12 volt connector and use a external power supply. Hopefully this helps someone. I also installed a switch to turn it on and off. I have external amps so I use it for a driver sometimes, by itself, or not at all depending what I put inline.