need tuner alignment on fisher 500c
- Thread starter ducati2
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You might want to try contacting Terry DeWick at DeWick Repairs; scroll down to the sponsor links at the bottom of the forum page.
thanks,, have an email to him now.. but sure would like to find someone in Oklahoma or north texas so I don't have to ship. I have several units to check. I would love to learn how to do it myself, but the consensus of the AK crowd is saying it is too difficult. I have time, brains, patience and funds for equipment, but nobody seems to pass on the skill.
roberts67
Volts Vinyl Tubes
Hello!
I understand your pain. I tried for months to get someone to teach me how. Once I really figured out what was really required I took my 500C to Inner Sound in Portland and they did a great alignment job for $79. I did buy some plastic alignment tools and an rf generator for aligning radios so I can start to learn the procedure. Peace. Robert
I understand your pain. I tried for months to get someone to teach me how. Once I really figured out what was really required I took my 500C to Inner Sound in Portland and they did a great alignment job for $79. I did buy some plastic alignment tools and an rf generator for aligning radios so I can start to learn the procedure. Peace. Robert
I would do the alignment myself (for myself to build skills) since I have rf generator, audio generator, and o-scope but I lack the MPX generator and distortion analyzer. If you have all needed equipment the by all means if you're adventurous, otherwise best to send it in.
yeah I have the plastic adjustment tools and an rf sweep generator, but that is it. I have a electronics teacher friend that is telling me that is all I really have to have, although a osciliscope should be the next purchase. he is to come over in a few days so we can play with it,, hope he knows as much as he says he knows.
I hope you have a good sweep generator, I have an old hickok and I have yet to figure out what I am looking for on the oscope.
I recently got a heathkit, FMO-1. It seems much more user friendly, I have been studiing the wave patterns it puts out and I think I am begining to understand it, this not a detected signal mind you just the 10.7 sweep directly into the oscope.
Really cool as you can see the two freq in my case you can count 6 distinct waves and 7 distinct waves and then there is the ghost waves that connect the two. All this being done on a 400 cycle.
I think if you really really wanted to do it right you would need a specturm analyser so you could see the actual IF freq, but I think the idea is to use the demodulated 400 or 60 hz pattern to get it right. My problem has been trying to get something that looks like the patterns shown in all the alignment procedures.
As far as MPX I have used a cheap little stereo generator (the kind used in cars to transmit to the car radio). I then hook up the two receiver channels to a dual trace scope, and then feed in an audio signal in to the FM xmitter one channel at a time.
I try to get as clean a separation as possible with as little adj as possible (it should be close unless someone has really messed with it).
My long term plan is to build a nice little integrated FM transmitter with adj audio generator, with a 3 way switch for FM transmit on L , R and L+R. also have a audio only out, that way you can hook up the audio out to one trace and compare to what is being decoded by the mpx one channel at a time. Vary the audio up and down the spectrum.
Of course using a rat shack cheapo xmitter is prob the big problem but still sounds like an interesting DIY project.
I recently got a heathkit, FMO-1. It seems much more user friendly, I have been studiing the wave patterns it puts out and I think I am begining to understand it, this not a detected signal mind you just the 10.7 sweep directly into the oscope.
Really cool as you can see the two freq in my case you can count 6 distinct waves and 7 distinct waves and then there is the ghost waves that connect the two. All this being done on a 400 cycle.
I think if you really really wanted to do it right you would need a specturm analyser so you could see the actual IF freq, but I think the idea is to use the demodulated 400 or 60 hz pattern to get it right. My problem has been trying to get something that looks like the patterns shown in all the alignment procedures.
As far as MPX I have used a cheap little stereo generator (the kind used in cars to transmit to the car radio). I then hook up the two receiver channels to a dual trace scope, and then feed in an audio signal in to the FM xmitter one channel at a time.
I try to get as clean a separation as possible with as little adj as possible (it should be close unless someone has really messed with it).
My long term plan is to build a nice little integrated FM transmitter with adj audio generator, with a 3 way switch for FM transmit on L , R and L+R. also have a audio only out, that way you can hook up the audio out to one trace and compare to what is being decoded by the mpx one channel at a time. Vary the audio up and down the spectrum.
Of course using a rat shack cheapo xmitter is prob the big problem but still sounds like an interesting DIY project.
