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DX2517 EDP690010Z Low RF Power First Time Posting. Really need some HELP,INPUT

You need real parts. Do you have a source? If not, I do.
You hit the nail on the head. I reorderd from ICA Manufacturing. The transistor is manufactured from HG. The unit keys up now. but i have a problem with Alignment.( A.M. is spot on). Both sidebands Transmit power, but i can't get them to realigned. Went thru the procedure. started with P.L.L. went O.K. then went to receive. it went O.K. Then started transmit. Could set the TX Offset Frequency no problem, then the next step is TX Carrier Oscillators. Can't get any to work from t est point 5&6 Can't ajust should be in the 10.6 range fore all non will ajust to no lower than 10.710 won't go any lower???? Any help would be appreciated again. Hate to give up now.'
 
You need a sensitive RF probe that won't load those test points down to read them. Another option is to inject a 1 khz tone while transmitting and adjust for 27.204 mhz for LSB and 27.206 mhz for USB while reading the transmitter output from the antenna jack into a dummy load. That's how I did it before I got an active RF probe.
 
I gave up on making frequency counters tap into those radios for a stable reading. If you have a ham transceiver with its frequency reasonably calibrated, tune in the frequency you want to set, like 10.6975. But set the radio to LSB and tune to 1kHz above, 10.6985. There's an app out there that will generate an accurate audio tone from your smart phone. Set it to 1 kHz. When the radio's trimmer cap is set on frequency, the tone from the receiver will be 1 kHz. You can compare that by ear with the tone from the phone's speaker. Like tuning an instrument with a tuning fork, you'll hear the pulsating "beat" betwee the two audio tones, getting slower and slower as they get closer and closer to being the same pitch.

One thing that annoyed me about using a counter and a probe was the error a probe would cause when you unclipped it from some (not all) test points. When I first heard that pitch in the receiver audio change as the counter's probe tip was unclipped I swore off using counters for that.

Naturally, if you don't have a calibrated receiver on hand, this advice is useless. Worth thinking about, at least.

73
 
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You hit the nail on the head. I reorderd from ICA Manufacturing. The transistor is manufactured from HG. The unit keys up now. but i have a problem with Alignment.( A.M. is spot on). Both sidebands Transmit power, but i can't get them to realigned. Went thru the procedure. started with P.L.L. went O.K. then went to receive. it went O.K. Then started transmit. Could set the TX Offset Frequency no problem, then the next step is TX Carrier Oscillators. Can't get any to work from t est point 5&6 Can't ajust should be in the 10.6 range fore all non will ajust to no lower than 10.710 won't go any lower???? Any help would be appreciated again. Hate to give up now.'
Either your carrier oscillator crystals have drifted out of tolerance with age, or as others have said here, you are loading them down. I use a spectrum analyzer with a scope probe to sniff (no contact) the oscillator for highest level and adjust frequency error accordingly.
 
I Have a Hantek scope but it won't pick it up properly. all the other alignments came out perfect except,theTX Carrier Oscillator.. thanks for the responce on this issue. . Maybe that crystal is off frequency enough to throw the frequency out of range for me to ajust properly.
 
I Have a Hantek scope but it won't pick it up properly. all the other alignments came out perfect except,theTX Carrier Oscillator.. thanks for the responce on this issue. . Maybe that crystal is off frequency enough to throw the frequency out of range for me to ajust properly.
A scope is not going to do it. You need to sniff the oscillator, so a spectrum analyzer or sensitive frequency counter is what you need. Try touching the probe to the can of the crystal
 
Setting a frequency adjustment requires some sort of way to measure or compare the frequncy that you're adjusting when you turn the screw.

A frequency counter is some folks' tool of choice. I prefer a receiver that has its frequency calibrated to "eavesdrop" on the frequency being adjusted. Hooking a probe into a circuit to read frequency with a counter can alter the circuit and throw off the adjustment. Doesn't always, but it can.

73
 
A scope is not going to do it. You need to sniff the oscillator, so a spectrum analyzer or sensitive frequency counter is what you need. Try touching the probe to the can of the crystal
That particular crystal has a bare wire that goes to ground.
 
WELL I FINALLY GAVE UP ON THIS RADIO. I REPLACED THE 10.6975 CRYSTAL AND IT HELPED MY ALIGNMET ON S.S.B. a lot but still couldn't get the upper and lower side to spec's. I'm done needs some one who is a E>T>Tech. to fix radio. I got it close but too many problems. The owner doesn't have the money to ship it out and back to a real tech. It's too costly because of size and weight. We have a Christmas get together every year in my area. Where we meet with our group and exchange or sell our overage and INFO . Suppose to meet a New Person who does radios, maybe he can fix problem. The radio is spot on on A.M. But sideband needs some help ,anyway this will end this post. and ( Thanks to anyone who added Input to this post. it helped.) At least it keys up and will transmit now.
 
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WELL I FINALLY GAVE UP ON THIS RADIO. I REPLACED THE 10.6975 CRYSTAL AND IT HELPED MY ALIGNMET ON S.S.B. a lot but still couldn't get the upper and lower side to spec's. I'm done needs some one who is a E>T>Tech. to fix radio. I got it close but too many problems. The owner doesn't have the money to ship it out and back to a real tech. It's too costly because of size and weight. We have a Christmas get together every year in my area. Where we meet with our group and exchange or sell our overage and INFO . Suppose to meet a New Person who does radios, maybe he can fix problem. The radio is spot on on A.M. But sideband needs some help ,anyway this will end this post. and ( Thanks to anyone who added Input to this post. it helped.) At least it keys up and will transmit now.
MIght be a bad crystal filter
 

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