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Who works on Texas Star amps?
- Thread starter Lkaskel
- Start date
'that's great, is there a diagram with the parts locations?
I
I'm trying to see how to get the picture's out of my file's on my laptop.
Hope this one work's Let me know
Also you need to check the bias before you put RF into the amp or it will blow those Transistor's. 0.676 / 0.68 Bias Volt Setting would be good. I would've put HG2879's in there to replace those DEI's they would run better and also, I would replace the Output Capacitor's with 1000pf Metal Clads. Test the Input SWR normally there set pretty good already then check the Output power with the Cap that's in there. If you could remove the Caps you could use a 1000pf Silver Mica Cap to test it to see if there's difference in Output power. Eiter way that should keep the Reflect low between the Radio and Amp. I hope this will help Let me know.
This is how you set the Bias Volts for these Amps.
Well after a near complete disassembly, trace repair, some parts replacements and tons of cleaning this is where I'm at. Much better looking than where it started and slowly getting it back together with little times available.
Please don't be too harsh with the criticism.
Please don't be too harsh with the criticism.
How'zit by looking at the combiner it shows signs that it got hot. If you test that 100ohm 2w metal oxide resistor it might be bad and it will blow those DEI transistors in that section. The splitter on the input should be alright. Do you have a transistor tester like those DS55 or so? I would test those transistors before putting everything back together. If it's okay what's your email so I can drop you my number.
Nothing ever got hot, it was never even powered up. There was tons of flux all over everything but after it was all cleaned up was all good. Report comic soon.
Cool brother almost there then. Just watch that video to manually key the amp and set the bias before you hookup the radio to it. Then it should be all good.
Gentlemen, it turned out to be a success. All assembled, checked bias impedance and voltage and checked good.
Pass through tune about 1.2:1 and with amplifier on it actually was just a tad lower at about a 1.1. With about 4 watts in I got about 100 watt carrier with little swing because the test radio swings very little and the power supply peters out. So far so good. Tomorrow I'll put it on the bigger supply with a swinging radio to see if anything gives but I don't expect it to.
I appreciate all of your help Gentlemen!
Pass through tune about 1.2:1 and with amplifier on it actually was just a tad lower at about a 1.1. With about 4 watts in I got about 100 watt carrier with little swing because the test radio swings very little and the power supply peters out. So far so good. Tomorrow I'll put it on the bigger supply with a swinging radio to see if anything gives but I don't expect it to.
I appreciate all of your help Gentlemen!
I'm looking and I can't see the catastrophe that was. You seem to have done a bang up job it looks great!
You still shouldn't have had to go though all that but you've made lemonade out of the lemon!
You still shouldn't have had to go though all that but you've made lemonade out of the lemon!
Thankfully that was the case my friend. Makes me wonder though, if I had been a regular consumer and just put power to it. 2 broken traces, the delay diode was incorrect, the electrolytic leg not even on the pad, blobs galore creating shorts...... how would that have turned out for an everyday consumer? It may have let out magic smoke, not operated at all, who knows.... and what kind of support would they have received? It really is sad!
Thankfully, I have some abilities and the fine folks of wwdx to help a brother out!
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Some of you were following my fun with the dx500 that in the end turned out well.
So today I received a surprise package from Texas star with a complete parts list aside from the transformers or pills. Not too shabby in the end to have replacement parts for if ever needed!
So today I received a surprise package from Texas star with a complete parts list aside from the transformers or pills. Not too shabby in the end to have replacement parts for if ever needed!
Good to see that, I am surprised to see the switch gang included.
It restores some faith that they did not leave you hanging.
Still makes you wonder about testing before they get shipped.
73
Jeff
Yeah I was surprised to see the switch bank and meter in there too. Hey, in the end I'm appreciative that they didn't leave me high and dry.