Wondering what test point to use for adjusting LSB, USB TX frequency. Do I use TP1 or is there another location?
The manual I have is confusing.
https://db.tt/bu3RvpaC
The manual I have is confusing.
https://db.tt/bu3RvpaC
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Alignment point for Texas Ranger TR-296
- Thread starter Mudfoot
- Start date
the way I am uderstanding it is you are testing the freq out the radio at the so239 connector since you have to inject a tone into the mic gain for SSB settings.
I just looked at the 148 and it shows tp14 to set the output feq. I have a tr296f I am getting ready to align. may do it in awhile and let you know what I do. just putting a tone out for ssb would get you on freq better if you have the equipment to do it with.
m42duster, not sure if you still need to know, but the way to do it is to first adjust the VCO outputs using TP1 like the manual says.
that part is pretty straightforward.
then, what you are really doing is setting the IF freq in each mode.
the reason they tell you to do it by injecting a tone is because the signal in the radio at TP3 is so faint that most counters will not pick it up without some kind of amplifier.
so instead, set your tone gen for EXACTLY! 1000hz, hook the freq counter to the antenna jack, (i like to remove the wires that are used for the bias adjustments from their test points so the radio is not actually putting out any power that could hurt the freq counter) and inject the tone for the SSB adjustments.
the AM adjustment is just using a dead key.
if you were on channel 20, it would be like this:
LSB-inject 1khz tone- freq counter to antenna jack- adjust L30 for 27.20400mhz.
USB-inject 1khz tone- freq counter to antenna jack- adjust CT2 for 27.20600mhz.
AM-no tone-freq counter to antenna jack- adjust L31 for 27.20500mhz.
hope that helps,
LC
that part is pretty straightforward.
then, what you are really doing is setting the IF freq in each mode.
the reason they tell you to do it by injecting a tone is because the signal in the radio at TP3 is so faint that most counters will not pick it up without some kind of amplifier.
so instead, set your tone gen for EXACTLY! 1000hz, hook the freq counter to the antenna jack, (i like to remove the wires that are used for the bias adjustments from their test points so the radio is not actually putting out any power that could hurt the freq counter) and inject the tone for the SSB adjustments.
the AM adjustment is just using a dead key.
if you were on channel 20, it would be like this:
LSB-inject 1khz tone- freq counter to antenna jack- adjust L30 for 27.20400mhz.
USB-inject 1khz tone- freq counter to antenna jack- adjust CT2 for 27.20600mhz.
AM-no tone-freq counter to antenna jack- adjust L31 for 27.20500mhz.
hope that helps,
LC
the only reason you have to inject the tone on ssb is because it will not read freq with out a tone. it just jumps all over the place. a buddy of mine has a shop here in Okla and has been doing this for over 40 years now and he can use his voice to get the tone just right and set the ssb freq this way. have checked his adjustment with a injected tone and he can get it right on with his voice. do not know how he does it but I guess it is he has done it so long he can. I try just with my voice and the freq counter just floats all over the place. and I am not long winded enough to hold the tone as long as mt buddy does. HA! HA! I keep telling him he is full of hot air.
sonoma, he must have seriously perfect pitch to be able to sing a 1khz note and hold it perfectly steady. 
im going to have to call shenanigans on this one though, because the human voice cannot produce a pure sine wave. our voices are a very complex waveform as we all know from watching a scope.
he mustve been zero beating the tone his voice made against another radio or something like that.
i have very good pitch, and can match a 1khz tone when i hear one, but it doesnt sound anything like a sinewave.
LC
im going to have to call shenanigans on this one though, because the human voice cannot produce a pure sine wave. our voices are a very complex waveform as we all know from watching a scope.
he mustve been zero beating the tone his voice made against another radio or something like that.
i have very good pitch, and can match a 1khz tone when i hear one, but it doesnt sound anything like a sinewave.
LC
well sorry you are not a believer , it is fact I called him on it on 2 of my radios and he would do it and I would inject a tone and it would be right on. if you read what I posted I did not believe either and that was why I ran the test after he did it with his voice. he uses a slight whistle also and he gets them right on freq.
I use this generator, a D-104 lollipop so that I can keep the mic keyed up (this also keeps my hands free for adjustments), point it directly facing the computer's monitor speaker, adjust my mic level, and then adjust USB and then LSB. No other noise/sound in the room when you to it, otherwise it will change the reading. It works. Also use the same process to tune/peak the TX coils in USB mode, except that I turn the mic gain down to read just 10w on a meter - then peak with the meter. When doing AM, I just turn off the generator and turn the mic gain down to '0' and then key it up; dead key with no modulation.
http://www.freesound.org/people/klangfabrik/sounds/28636/
http://www.freesound.org/people/klangfabrik/sounds/28636/