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At THIS point I'm saying LEAVE R44 whatever value is in YOUR radio. The thing to do is ensure you take the 8 volt side of it, and put it to the constant 8 volts. I BELIEVE that the difference in values can be attributed to either a different value of clarifier pot, OR it could be the used a...

Phil, The issue here is, class C is not linear amplification. As soon as you start applying enough bias for linear amplification, you'd need peltier junctions to keep the individual devices cool. And at that point, you'd be right back up to the cost of 2879s, and a single 2879 does a HELL...

Phil, I speak regularly with someone running the OLD WABC transmitter on 75. Those 'switchmode' transmitters are a trip. I've worked on one before, JUST one. Not real common. Those 600 watt modules should be run as 40+ modules, half for positive peaks, half for negative. They run a...

By NOT jumping D51 and R174, you have the mod that will give you an unlocked clarifier, and at the SAME time give you stock slide, about a kc up and down, give or take (each chassis slides a bit differently). The problem we had here was that pesky R44 and me forgetting to tell him to bring it...

If it is a GOOD shop, they SHOULD be able to center slot the clarifier for you. I've ALWAYS, on EVERY radio I've EVER done, center slotted the clarifier. To do anything else is just friggin GHETTO. No problem on sticking it out. I'd like to find the difference in the chassis, so we can...

I just went back and reread everything we had posted. R44 is supposed to be 8200 ohms. 8.2K , however ya wanna put it. Brainfart. BUT, the end that went to the 8 volt supply NEEDS to go to the 8 volt supply that you moved the red wire to, NOT the original spot where it was. Sorry...

Cutting out D52 disables the radios internal VR that controls TX frequency. You CANNOT have it in, and have an unlocked clarifier. The simple fact that you can slide a complete channel means something is fubar. You do NOT want to ground one side of the clarifier control. THAT is going to...

How? I get this every once in a while, and they are cutting out all the glazed and glass insulators here, going to covered insulators that won't be effected by ice. Interested in hearing how you found it, maybe if I can pinpoint mine, I can get SCE to replace THAT one next (PRAYING!!!)...

I personally know more than a couple MRI technicians. NO, I don't have a good line on surplus tubes, lemme get that out of the way now. They already sell to Alan. BUT, the YC-156 IS going away, and as you stated, may be out of production already. HOWEVER, the 179 is still being produced...

The ERF devices where NEVER designed for RF service. They are designed for switch mode power supplies, if I remember correctly. Mr Bulldog Wattmeters just found another way to make profit. Not many people that KNOW how to interpret what they see on a scope... And using an exciter tuned...

359, Also, the EASIEST way to run a tetrode is to run it grounded screen. Then you return the power supplies to the cathode and associated circuits to ensure the internal elements are STILL seeing the proper ratio of voltages, but as shockwave pointed out, you have problems with the screen...

People typically run 38 as the call channel, but as someone else said, it does change regionally. Haven't heard anyone on 16 since I moved out of the high desert the first time in the 80s.... But, yeah, you pretty much got the mod down. --Toll_Free

R44, if present, is 800 ohms in my chassis.... HOWEVER, I'm NOT on a 'current' rev chassis. It may be changed to an 8.2k today...... If you HAVE R44 installed, LEAVE IT ALONE, it's where it's supposed to be. Some of the variants I've seen had a jumper. Hence me pointing out if it's...

Almost all tetrodes need neutralization. It's the nature of the gain. I've also built single sweep tube drivers (grid driven) driving 3-500s before. It was JUST about as much of a PITA as building 4-400s... Actually, the 4-400 as a tetrode is BETTER than an 8950 or 6??6 driving a 3-500...

Wake up and forget to have your cup of humor this morning, Mack? --Toll_Free

The BEST method to rework the clarifier in the 148 is this: Remove the 8 volt receive wire on the clarifier. This color depends on year / vintage / country, so I can't help you. BUT, it will go to a wire that will have 7.9 or more volts on it IN RECEIVE ONLY!!!! Find a spot on the board...

"Most MOSFET CB Craplifiers do tend to run warm" There, fixed that for ya Mack. NONE of my RF FET amps run warm at ALL. It's this switchmode garbage that people think works on the CB that runs warm. Running a device into saturation will ALWAYS cause that to happen :) As 443 pointed...

You want the GODS honest truth? 1. Nobody will pay for them. The tet's, while NOT needing the associated driver, need A lot of protection. Protection = $$$s. $$$s and CBers don't go together. 2. You actually OPERATE a tetrode. You MUST pay attention to the screen voltage and grid...

Tony said a pair of ANY tube wasn't the best choice. I have the email where he said a single 3CX3000 is BETTER than a pair of GS35s. Although he was a CHEAP QRO operator, he also believed in honest engineering. NO Engineer will tell you a pair of tubes is better than one. That's stupidity...

I been accused of BEIN sticky before, but this is my first time IN a sticky!! :) This is the BEST method of lowering the carrier in any solid state transformer coupled radio. The JP3x mod, TRASH. Anyone who owns a scope will NEVER perform that mod again, after seeing before and after...