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Farad Capacitor?

The cars electrical system still has to charge up the capacitor as well as supply operating current for the device being powered. IMHO a cap is a bandaid at best. Proper alternator rating as well as the proper sized cables are what is important. If you need to run a capacitor to supply proper power then you are either running too much power or are not doing it properly. Either way a cap is 100% useless for an AM radio and only moderatly usefull for SSB.
 
There is nothing better than doing test to see if it works.

Record some statistics with and without the capacitor hooked up. Some things like voltage, amperage draw, amplifier wattage and also some receive and transmit reports from known reliable stations.

It may or maynot help, only you can decide when you have the information in front of you.

If it works for you that's all that matters.
 
" Adding a 1 farad capacitor across the power leads of a linear amp in mobile operation is an absolute necessity as far as I'm concerned. The capacitor performs two functions: first it will act as a noise filter and improve the receive performance of the transceiver. Second (and most importantly), It will act as a current sink and help provide maximum available amperage( and eliminate system voltage drop ) under peak load conditions. Users of super high power car stereo amps use several of these to keep their amps from clipping under peak load. Same thing applies to CB linears. Go for it ... you will see a BIG increase in power output and audio intelligibility.
"

Sorry but I'm not buying it. Your bat-cap will be empty in 2 seconds worth of dead key. Thats why they work well for car stereo amps. The steady drum beat gives the cap time to recover. A cb amp has no drum beat. At best it will give you alittle filtering.
 
I agree with them being pretty much useless on straight AM, but I know they work on SSB. On AM you've got a continuous high current draw because of the carrier...on SSB, you have no carrier to speak of and your current draw is in spikes (mimicking modulation)...

I have two 1100CCA batteries, 135A alternator, and 4Ga wire from the batteries to the amp. The amp is a 4-pill...4x1446. Without the cap, the lights would bounce/dim with modulation on SSB. After the cap (just a single 1F stereo cap), no more dimming on SSB. It made no difference on straight AM...

Just my findings. Not sure it did anything for TX/RX, but I was more worried about the potential damage to the alternator from the current spikes, which the cap significantly reduced.
 
This can give you more "pep" or swing, if you keep the dead key low. Meaning the dead key would need to draw less amperage, to give the alternate enough room to charge the capacitor while keyed, then when you modulate, t he capacitor would store enough, to maintain higher voltage.. How successful this would be, would depend on how large the capacitor is, in relation to the amount of extra current needed during these spikes..

Capacitors do a great job with keeping voltage up, but more as a short term/instaneous gain.. Similar to RAM helping a computer run more smoothly, in relation to a strong processor.
 
OK guys I know this is a very old post I just purchased a galaxy DX 98 vhp around 300 watts was wondering about these amp compacitors my truck has a 180 amp alternator running radio with 4g wire would a compacitor help or just a waste of money and my 180 amp alternator do the job thanks
 
The EMP the caps could generate may leave a hole in the trunk if they ever failed.

Just not sure if RF and DC playing back by your gas tank is really a good idea - RF inside the car across one of those cap-banks may cause gassing issues - not from the amp proximity, it's the draw of the amp and it's own RF power leakage - if too excessive, may leave you disabled...

I'm referring to shielding. IF these are not shielded or even rated, bail out on the cap idea and let the Alternator and a battery isolator, spare battery setup, do the trick better.
 
What we learned in car audio is that they can help if your charging system underpowered. But they are a bandaid and will help your alternator run at full output for a longer duty cycle and are blamed for killing alternators. Nobody uses them anymore because of this. The real solution is to get a bigger or second alternator and more batteries.
 
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this radio shows to pull 40 amps at full output from what I have read about it. I believe it even comes with a 40 amp fuse in it.
 
Check the voltage with a meter at the radio when you key it. If the voltage drop is acceptable to you then you are good to go. If it sags too much then check the voltage at the battery when keyed up. If the battery voltage stays up and the radio voltage dips then you need bigger wire or might be a bad connection.
 
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The only Farad capacitors that I ever found useful for my needs are the little 1 farad 5.5 volt ones found inside some programmable radios . They hold a charge long enough to keep your programmed memory intact while the power is temporally disconnected.
 
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