Sidebar Sidebar
  • You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

texas star 500


D3 might have been put in there to protect the amplifier from reverse polarity. However the fusing appears to be of 70-amp rating, so its possible D3 blew up before the fuses and destroyed the amplifier.

I think L1 supplies power to the RX preamp
 
My total humble
condolences to your friend ethomas :( Not the best of ways to start off the new year. It hurt just reading that . :( I've seen that same part go in the 350s in the past and it DID NOT effect the transistors. TexasStar is in Escandito S.Cal , if ? you can call them and get a RMA number , they will repair it for you for next to nothing or slightly something. IM no amp guy , but I think there's a good chance the transistors are OK , it would be L1 and a few other parts. (if he's lucky) The best of luck to you.
 
Last edited:
ethomas said:
My buddy brought his 500 dx over was going to hook up and see what it was doing on meter. Then he hooked the + to the- just touched it a small spark. And when he hooked it up right i keyed up and smoke L1 was fried and help?
Anyone had this to happen?????
http://www.cbtricks.com/Amp/txstar/dx400_dx500/graphics/dx400-dx500_inter_connection_layout.pdf
Click to expand...

Tricky CB Schematics.

The schematic on that tricky site cannot be trusted, it shows a great oscillator but not the true amplifier as it is ran; important details have been omitted.

When amplifiers are run with some amount of + volts on the bases it is common to use the relay to switch the supply volts to the voltage divider circuit for the base bias. The volts are applied (via an inductor) through the same contacts that the RF signal goes through; on the "other side" of the relay, the DC volts are picked off with another inductor. The RF signal goes to the splitter while the DC volts go to the bias circuit.

Replace the inductors and see if it burns again at activation of the relay; if so, your final transistors are drawing excessive base current and they are TOAST.
 
Happy New Year Paws , now if I could understand all that , I'd be really good. :tongue: But like I said , at the time , I got this Texas Star 350 used , I have no clue what had caused the problem with torid being burnt up and the amp not keying up at the time ? I replaced the torid only for it to fry right in front of my eyes :(

this was a few years ago , I got a RMA # from Texas Star and sent the box in to them , (can't remember the tech's name over there) but they fixed it for nothing and shipped it back to me on there dime. It was the torid (or choke or whatever the hell you call it ?) and a few other minor parts , the transistors were fine and not replaced.

IM finding it hard to believe (with my little know how) that a quickie hook up backwards effected this 500 like that ? Now I've changed the protect diode in a few amps in my time , but even then , the transistors were fried :( and this guy only is stating about the torid , I wonder if the dude could post a close up of his buddies amp board ? sometimes those diodes go but they don't look like it by just looking at them.

I suppose IM just trying to be positive here where this guys transistors are concerned. It's really hard to say with what little he has told us. Even if it were the transistors , if the guy can get a RMA number from Texas Star , they would be his best bet at getting it repaired at the cheapest cost possible. (transistors or no transistors)
 
paws264 said:
Tricky CB Schematics.

The schematic on that tricky site cannot be trusted, it shows a great oscillator but not the true amplifier as it is ran; important details have been omitted.

When amplifiers are run with some amount of + volts on the bases it is common to use the relay to switch the supply volts to the voltage divider circuit for the base bias. The volts are applied (via an inductor) through the same contacts that the RF signal goes through; on the "other side" of the relay, the DC volts are picked off with another inductor. The RF signal goes to the splitter while the DC volts go to the bias circuit.

Replace the inductors and see if it burns again at activation of the relay; if so, your final transistors are drawing excessive base current and they are TOAST. NOCODEHAMSARELAZY
Click to expand...



LOL'D

foodstampft6.jpg
 

dxChat
Help Users
  • No one is chatting at the moment.


      Top Bottom
      Back