Texas S Dial A Watt Potentiometer Replacement Suggestions ??

[Wire Weasel]

I'm not having an issue, but remembering many stories about the factory Pot on 667 & 500V's going bad and was due to the pots not being heavy duty enough or something. Googled for an article but didn't see anything. Anybody here remember the issue and What Value Replacement pot is better that will hold up to job it is doing? Thanks !

 

[groundwire]

its no different than any amp with a variable. put to much carrier into it and the pot burns up. you got two choices replace it with the typical 5w pot or bypass it altogether. i would choose #2. variable pots are a weak point in amplifiers and in my opinion dont belong there. adjust input power at the radio not the amp.

 

[AudioShockwav]

My 500v is well over 20 years old with the factory variable.
It is always wide open and I always set the radio to drive amp.

73
Jeff

 

[999]

My 667V is probably 35 years old and I've owned it since 1996. It has TWO THIRDS KILOWATT on the front. No issues with the original variable, but I never run the variable anywhere but wide open.

 

[nomadradio]

I never run the variable anywhere but wide open

That's what we recommend to customers. As a rule you won't blow out the control so long as it remains at full bore drive level. Set the carrier with the knob on the radio.

And if your radio doesn't have that knob, you're taking a chance.

73

 

[Tokin]

Unfortunately like everything else quality potentiometers have disappeared and whats left of the old quality parts are expensive if they're even available. Shit an arco 425 is $30 if you can find one.
Ive talked to countless old school amp techs and they all say the same thing, once the parts supply switched from Japan to China it all went to shit. Older units with better quality parts that arent over driven and variable left wide open will last the longest.
Search the hamfests for nos and used parts otherwise buy a fist full of chinesium and be ready to replace it as soon as it starts feeling scratchy when you turn it. If it feels like its full of sand its on the way out.

 

[144inBama]

Myself, I'd use Allen Bradley. EXTREAMLY robust and easily acquired.

A&B 250 Ohm.

 

[nomadradio]

Wow! I had no idea the type J is rated at two and a quarter Watts. Always thought it was a two-Watt control.

Remember that this rating is for the full length of the resistance element inside. If you turn it to center position it's a 1-1/8 Watt part. Turn it down to the 25 percent setting and it's a half-Watt part, more or less.

This is why we tell customers to just turn the control full up on Texas Star models that have this control. It seldom fails so long as you maintain that discipline.

73