What I've done is...
Once you find a power level that is acceptable to the Amp and you...
We have two choices, you and I -
Keeping the Variable control
- Remove the pot, and install a FIXED divider in it's place (BEFORE the input reaches the board FROM THE POT (the Divider? There's a reason for that...)
- Install a BUFFER resistor of about 10 ~ 15 ohms at 2W rating IN series (In line) with the pot and it will act like a lower dead key variable.
- JMHO - this option is better for the amp - because it never sees peaked PEP if your radio was a MOSFET conversion with limiter removed, the potential power swings can throw the Amp too much peak power and damage those Bipolars...
- - you will wind up getting something like a 15 ~ 22 ohm 2W resistor in line with the feedline to the input (internal where the pot would be) - then attached ACROSS it at the connection to the board, is a 150 ~ 220 (2W) ohm BLEEDER resistor to ground (strapped) to again lessen the vari-key impact of swing into the amp.
- The Divider can be installed BEFORE or AFTER the POT, before it's TAPPED output goes into the board - so the POT sees more resistive output and NOT SINK all the wattage going into the amp
In regards to the Divider...
The
Divider setup is more for MOSFET driving Bipolar Amp design...
Once you have decided to run FIXED NON-variable - this is when you have a Vari-key Mod like JP-36 and Swing Mod like NPC-RC at the radio and you just want the amp to be a set it and forget it...
- You have to determine the level of drive but keep your Tech in the loop ok? Because they will need to know where the DIAL setting of the POT is so you can show them - I WANT IT HERE for BEST RESULTS
- They then can take out the pot, read the ohmic value, and install the proper resistive FIXED value and if needed in MOSFET converted radios - a BLEEDER resistor of a higher ohmic value (See Above) of same wattage (2W) is attached and applied across the input from the output end of the Buffer resistor to ground to remove a lot of the PEP drive that can get those Bipolar units hurt and fail fast...again only for those MOSFET Finals' to Bi-polar amps.
- - you can then run your SSB levels (if so equipped) or Mic Gain (Dynamike) as you see fit to drive swing into the amp
- - you will wind up getting something like a 15 ~ 22 ohm 2W resistor in line with the feedline to the input (internal where the pot would be) - then attached ACROSS it at the connection to the board, is a 120 ~ 150 ohm BLEEDER resistor to ground (strapped) to again lessen the vari-key impact of swing into the amp.
- In this setup you no longer have the Variable at the Amp, your variable is at the Radios Power settings and swing methods of power delivery - BACK AT THE RADIO. Your amp has been swamped with some resistive elements to reduce the dynamics of the radio from potentially damaging your amp when you get careless or too drunk to care - which if you're prone to that type of activity - is BOUND to happen.
If you're into Competition Comp Stomp stuff - then obviously this mod won't apply to you. Run it as you wish...
In That Case...
- Just ask yourself - "Why if I'm here for Full Throttle Action - why do I need a Variable?" - and act accordingly.
I'm only offering this because as those T/S age, (any Bi-polar amp really) the pots are harder to locate and their costs are going $$$ up and they have to accept the outputs of MOSFET's output radios become more the norm, you need to do this.
Else the older Bipolar to MOSFET conversions on a simple regular AM-Only (2078) or simple SSB with nothing more than a 16 watt PEP (2312 or 1969) setups are now replacing them with MOSFET, they are a little too much power PEP for the Amps to take like the older days of even a limiter-off full-bore Bi-polar breathing fire into the amps Input.
I mean, its' your money - but why throw it away in smokes?
