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 Post subject: Newcomb Model AVTS
PostPosted: Apr Sun 08, 2012 5:29 am 
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Joined: Dec Tue 19, 2006 11:09 pm
Posts: 74
Location: Oklahoma City
I just received this cool old record player today and of course started the preliminary inspection. Obviously the caps will need to be replaced but it has some odd problems that I thought I would toss out there and see if any direction can be given here.

The auction number was 320859876066 if you would like to see pics. I am on my iPad so harder to deal with Getting pics off of eBay to the iPad to the forum.

Anyway, after resoldering the wires on the cartridge, I have both channels. I suspect the caps in the preamp are bad as there is very little power coming through but powerful hiss when turning up the volume. But when playing a record, very little sound and very buzzy/distorted. I am replacing the cartridge as well as the caps and hopefully it isnt transistors.

The cartridge leads feed directly into the balance control but I have no contr ol over the balance. The sound does not change when rotating this control. I checked for direct shorts but was not able to locate any. Is this a tin whisker problem?

I remember these units putting out a lot a good sound and hope for some guidance on this old gal. Thanks everyone.

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Roy
(RCAkid)
_________________________

Ahh, the power of tubes.


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 Post subject: Re: Newcomb Model AVTS
PostPosted: Apr Sun 08, 2012 10:56 pm 
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Joined: Dec Sun 07, 2008 7:05 am
Posts: 4238
Location: MS
The hum & distortion problem is probably due to bad electrolytic capacitors. Go ahead and change all of them.

What you describe with the balance control sounds like a whisker shorted pot or a problem with the cartridge wiring. I think these use an Astatic 13T stereo powerpoint cartridge. If not, the correct type number should be printed on the instructions pasted inside the unit. Check to make sure the cartridge installed is what's supposed to be in there.

If it uses a 13T, you might want to replace it with a current Pfanstiehl P228, or similar cartridge. This will require soldering and adjustment of the tonearm tracking force spring; but, 13T's are no longer made and the remaining NOS units often have age related defects.

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 Post subject: Re: Newcomb Model AVTS
PostPosted: Apr Fri 13, 2012 12:32 am 
Member

Joined: Dec Tue 19, 2006 11:09 pm
Posts: 74
Location: Oklahoma City
Thanks for the info! Can't say I am looking forward to tearing those pots apart but fining the exact type of control has been difficult. So popping them open and cleaning them out seems to be in order. The bass and treble don't seem to have that issue, just static and a bit of deoxit will solve that. The volume may have tin whisker issues as well. Will try deoxit first and see what happens as the volume control works but seems a bit odd in its travel.

Ordered the P228 cartridge as you suggested, from V-M and the caps from AES.

Hopefully she will be flying again and sounding solid. I have only ever heard the mono units and they had massive sound. Looking forward to hearing this stereo machine.

As soon as I get her up and running I will post an update.

_________________
Roy
(RCAkid)
_________________________

Ahh, the power of tubes.


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