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Texas Star 250HDV

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  #1  
Old 04-03-2009, 04:31 PM
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Default Texas Star 250HDV


I have a brand new TS250HDV and when I power the amplifier on, the relay automatically engages, making it impossible to receive anything. I tried 2 different radios, mics, coax and power sources, but with the same problem. Anyone have any suggestions? I'm pulling my hair out!


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  #2  
Old 04-03-2009, 04:51 PM
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I'm no tech; but you are going to need a schematic for this one.

You will need to trace the relay circuit and find voltage entering in along at some point that is keying the relay on. Something is giving it voltage when it isn't supposed to get it - obviously. With a voltmeter and a soldering iron, isolating each part and eliminating one by one will expose the problem - but it will be time-consuming and effective.

Other than that, someone else that experience with that unit will have to point out where in particular to look for the problem source...
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  #3  
Old 04-03-2009, 05:39 PM
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Default Was it converted before purchase?

Texas Star CW Transmitter To RF Amplifier Conversion


Model DX250 & DX350
  1. Remove yellow 2200K cap of the oscillator board from the PCB
  2. Remove red wire of oscillator board from RF choke
  3. Remove green wire of oscillator board and attached 33pf cap
  4. Solder the leg of 15 or 18pf cap to input trace on PCB
  5. Remove black wire of oscillator board from keying jack
  6. Remove oscillator board
  7. Locate jumper wire attached to backside of red switch
  8. Unsolder the ground end of jumper wire closest to the relay
  9. Solder this end to bare lead of 10-ohm resistor behind red switch
  10. Remove 10-ohm resistor piggy-backed to 15K resistor located next to the white sand block resistor and RF choke
Was this work done prior to your purchase?
This may be a stock CW transmitter and not setup yet to work as an amplifier. I found this info on-line so not sure if it 100% correct.
All the Best
BJ
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  #4  
Old 04-03-2009, 08:15 PM
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BJ-
Yep I saw those instructions also. It seems that my amp was successfully converted. It matches up to the instructions here. A few people had mentioned it may have a bad keying transistor, so I'm going to change it tomorrow and see what happens!

Quote:
Originally Posted by BJ radionut View Post
Texas Star CW Transmitter To RF Amplifier Conversion


Model DX250 & DX350
  1. Remove yellow 2200K cap of the oscillator board from the PCB
  2. Remove red wire of oscillator board from RF choke
  3. Remove green wire of oscillator board and attached 33pf cap
  4. Solder the leg of 15 or 18pf cap to input trace on PCB
  5. Remove black wire of oscillator board from keying jack
  6. Remove oscillator board
  7. Locate jumper wire attached to backside of red switch
  8. Unsolder the ground end of jumper wire closest to the relay
  9. Solder this end to bare lead of 10-ohm resistor behind red switch
  10. Remove 10-ohm resistor piggy-backed to 15K resistor located next to the white sand block resistor and RF choke
Was this work done prior to your purchase?
This may be a stock CW transmitter and not setup yet to work as an amplifier. I found this info on-line so not sure if it 100% correct.
All the Best
BJ

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  #5  
Old 04-05-2009, 05:56 AM
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sounds like the keying transistor is shorted.
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  #6  
Old 04-05-2009, 06:20 AM
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if it's "brand new".... why don't ya just get your $$$$$$ back?

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Old 04-05-2009, 09:22 AM
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Quote:
Originally Posted by hookedon6 View Post
if it's "brand new".... why don't ya just get your $$$$$$ back?
Then it would'nt be (cbing) now would it?

The relay is seeing a path to ground on the coil so most likely the transistor has gone short and is easily replaced with minor soldering skills.

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  #8  
Old 04-05-2009, 10:00 AM
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Thanks to all who advised. I brought it back to where I got it and the shopkeeper hooked it up and said, "You have a bad keying transistor...here's a new one" he tested the new unit for me and all is well. Thanks for the info guys!

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