That chassis the OP stated was a "632-11"?
That's a Sams Photofact number, not the RCA Victor chassis number of RS-1205 (A/B/C) - stamped on chassis.
Sams has been known by us techs as having frequent mis-prints.
So we stick to using the original RCA service manuals, rarely a misprint.
Beitman's manuals have them in DjVu, and I use them when needed.
And as I said previously, the RS-1205C chassis in my console was a bear to work on.
Also, the filtering caps are strategically located and grounded - making any changes to that will majorly result in poor operation.
That's a Sams Photofact number, not the RCA Victor chassis number of RS-1205 (A/B/C) - stamped on chassis.
Sams has been known by us techs as having frequent mis-prints.
So we stick to using the original RCA service manuals, rarely a misprint.
Beitman's manuals have them in DjVu, and I use them when needed.
And as I said previously, the RS-1205C chassis in my console was a bear to work on.
Also, the filtering caps are strategically located and grounded - making any changes to that will majorly result in poor operation.
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You are right, the amp is a Rs-199a and the tuner is a rc1205a. They are from an rca IVF-306a
I swapped a few tubes around between some spares I have from a few magnavox tuners. Nothing.
Removed the tuner and was examining it, this pulley quits putting tension on the white string right around where I stop getting channels. I haven't done anything yet, waiting to here any tips or tricks. I'm guessing it became loose when putting it back in the console.
The one thing I never liked was that old style FM tuning string arrangement.
It's extremely sensitive to being mis-adjusted.
The RCA manual explains the critical procedure.
Luckily, my RS-1205C has a traditional style tuning capacitor for FM, a seperate one for the AM.
It's still a bear to align.
You'll need an O'scope, RF signal generator, accurate VTVM, and the proper alignment tools, along with the complete alignment chart.
If those are not on your bench, all the online speculation in the world isn't gonna help you.
It's extremely sensitive to being mis-adjusted.
The RCA manual explains the critical procedure.
Luckily, my RS-1205C has a traditional style tuning capacitor for FM, a seperate one for the AM.
It's still a bear to align.
You'll need an O'scope, RF signal generator, accurate VTVM, and the proper alignment tools, along with the complete alignment chart.
If those are not on your bench, all the online speculation in the world isn't gonna help you.
The FM tuner in these was pulled by a string. No "push" action. When dust, cockroach, etc gets stuck in the works, only part of the range works.
He stated that the FM worked after he changed all the parts, and it stopped working when he put it back in the console.....all that fancy alignment gear will not help you or anyone else fix a busted dial cord or a spring.
Are the stations that work in the proper place on the dial? It looks like FM tuning is done by pulling on the string that comes from the sealed box with the 6DT8 in it. That moves the tuning slugs inside a pair of coils to change the FM station. Something has messed up that action.
This is called permeability tuning, and was actually invented by RCA. The concept was taken to extreme in the R390A military radio receiver from the 1950's to the 1980's. It had about 30 tubes in it, weighed a ton, and the alignment procedure was a separate book, not a thin one either. It took me a whole day or more with the right test equipment. There were several vendors, and all were NOT identical.
DO NOT mess with the electrical parts inside that box. Don't even move a wire, much less a cap. Parts placement IS critical. Don't try to go inside it unless absolutely necessary. I do not know anything about your particular unit, but the FM tuning box was often serviced as a complete unit by swapping it out, especially in the early solid state years.
Are the stations that work in the proper place on the dial? It looks like FM tuning is done by pulling on the string that comes from the sealed box with the 6DT8 in it. That moves the tuning slugs inside a pair of coils to change the FM station. Something has messed up that action.
This is called permeability tuning, and was actually invented by RCA. The concept was taken to extreme in the R390A military radio receiver from the 1950's to the 1980's. It had about 30 tubes in it, weighed a ton, and the alignment procedure was a separate book, not a thin one either. It took me a whole day or more with the right test equipment. There were several vendors, and all were NOT identical.
DO NOT mess with the electrical parts inside that box. Don't even move a wire, much less a cap. Parts placement IS critical. Don't try to go inside it unless absolutely necessary. I do not know anything about your particular unit, but the FM tuning box was often serviced as a complete unit by swapping it out, especially in the early solid state years.
Thanks for the back story, very interesting and your claim is backed up by the parts listed. The multiplexer is listed as a single part and not sold by anybody else for a replacement!
The stations were not quite accurate, my easiest option as of now is to tighten that string, just one knot up. As long as it still moves the wheel near the end (where it wasn't before at the higher fm frequencies) then my plan is to set it at the highest channel I get and align the dial to that station. Then hopefully it's semi accurate from there. It's a hail mary but like I had mentioned before, I'm just missing a Christmas channel, this isn't going in a museum! 😀
Just a quick update, it was that string going into the multiplexer. I tried tying a second knot right next to the 1st to take some slack out, but even that small of an amount was then making me lose stations on the lower half.
What I ended up doing was moved the dial all the way to 108 as a frame of reference, used the original knot and inserted it into the slit and moved just that rod with the slit until it was taut (you could tell because the wire would finally start coming out of the multiplexer). Then once I turned the fm knob it began moving instantly.
The channels appear to still be pretty accurate on the dial.
I'm sure this thing could be turned in a little better, missing a few channels and some are much louder. I'll try to hook it up to my outdoor antenna tomorrow just to be sure.
What I ended up doing was moved the dial all the way to 108 as a frame of reference, used the original knot and inserted it into the slit and moved just that rod with the slit until it was taut (you could tell because the wire would finally start coming out of the multiplexer). Then once I turned the fm knob it began moving instantly.
The channels appear to still be pretty accurate on the dial.
I'm sure this thing could be turned in a little better, missing a few channels and some are much louder. I'll try to hook it up to my outdoor antenna tomorrow just to be sure.
Alright I've got one last question, and I know that a tune up is necessary at this point which is unfortunate because I have neither the money or equipment to perform such a task.
But please help me understand why this is happening!
I am finally getting everything from 107.5 - 88.1 however I have a strange problem and it may be my lack of understanding.
If I turn on the console and go to 104.1 the station is weak and soft, while others come in strong all the time. If I switch to AM and go back, 104.1 is loud and comes in great. After a few minutes the signal switches in a split second to how it was before, weak and softer.
I just want an understanding. Is it simply alignment? Why would it come in great and just shift to poor just like that?
Thanks for the guidance folks, I'm still in my 20's and learning but it's a slow process for me. Thanks for your patience as well
Imgur
Video for reference
But please help me understand why this is happening!
I am finally getting everything from 107.5 - 88.1 however I have a strange problem and it may be my lack of understanding.
If I turn on the console and go to 104.1 the station is weak and soft, while others come in strong all the time. If I switch to AM and go back, 104.1 is loud and comes in great. After a few minutes the signal switches in a split second to how it was before, weak and softer.
I just want an understanding. Is it simply alignment? Why would it come in great and just shift to poor just like that?
Thanks for the guidance folks, I'm still in my 20's and learning but it's a slow process for me. Thanks for your patience as well
Imgur
Video for reference
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And for my last bit of advice......
Tube sockets from 1960 become corroded naturally, as well as weakly holding onto the tube pins.
It's natural aging, like anything.
Asides from installing new sockets, the old ones can usually be cleaned, and carefully re-tightened to grip tube pins tightly.
I've done hoardes of "restorations" for customers over the last few decades, so I know the deal.
Over and out....
Tube sockets from 1960 become corroded naturally, as well as weakly holding onto the tube pins.
It's natural aging, like anything.
Asides from installing new sockets, the old ones can usually be cleaned, and carefully re-tightened to grip tube pins tightly.
I've done hoardes of "restorations" for customers over the last few decades, so I know the deal.
Over and out....