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I've gotten a chance to tinker a little bit more with the Westinghouse AM-FM radio I stumbled on yesterday and so far it's turning out to be a good radio. I checked all the tubes in it, which also gave me a chance to give the Sencor "The Hybrider" checker I bought a couple months ago a good test and all the tubes checked good with only the 50C5 worn down some. Even the original 12DT8 checked good, but the radio still seems to prefer the RCA tube I stuck in it yesterday. Although the radio uses a circuit board, it seems fairly roomy and the radio doesn't seem to hold excess heat in the cabinet. From what I can tell, there isn't much to go wrong as most of the capacitors are ceramic discs. Seems all that will need to be replaced are the selenium rectifier, the filter caps, and there are two other small electrolytic caps on the board. No signs of SMD and that little multi cap (can't remember it's name) seems okay. The only real issue I had was the band switch that, although didn't sound dirty, was very fussy until a couple of cleanings. I think I'll use this radio until I get my Zenith C845 finished and then get this one done. It plays pretty well for a virtually untouched 1960's Westinghouse. I do notice you want it really good and warmed up for weaker FM stations unlike my Zeniths which are good to go as soon as you get sound.
No matter where you go, there you are.
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I love that one Jayce, are the 12DT8's usually problems? I believe that one works in the FM for those style radios?
Paul
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12AT7 vs 12DT8 some books show they are a sub for each other WRONG! Pin nine on the 12DT8 goes to ground a internal shield. Pin nine on the 12AT7 is a center tap for the heater. I learned the hard way. David
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I have several AM FM tube sets and have wondered about the 12DT8 tube. Many times they play fine on FM but fade to weak on AM and I wonder what tube could it be especially on a recapped set, selenium rectifier taken out....any ideas?
Paul B
Tubetalk1
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Yep, the 12DT8 is the tube for FM and at least in Zeniths is worn out because they shut the plate off when you switch to AM, but leave the filament on. Not sure if the Westinghouse does that. In a way, I prefer the 12DT8 to the 12AT7 as it is a radio only tube and you aren't battling musicians and audiophiles for supply. The cheapest NOS 12AT7 on Tube Depot right now is roughly $25 while a NOS 12DT8 is $10. Probably better deals out there, but that was just a quick sample. Either way, I have wanted a nice Westinghouse AM-FM for a while and other than some wear and a couple of dings, this radio is in very nice shape if it has spent its life in NE Ohio. The plastic is so white that I think this radio saw very little or no cigarette smoke.
No matter where you go, there you are.
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Paul, I haven't had issues with 12DT8s on AM and the AM on the Westinghouse is fine, though the chunky rod antenna is very directional. Usually in AM-FM radios the 12AT7 and 12DT8 tubes only handle FM. A case in point is a couple clunker Philcos I have had that played great on AM, but no FM. The reason, both of them had dead FM tubes! One a 12AT7 and the later one a 12DT8. Also I've noticed on Zenith sets that if your FM starts to get weak while AM is good, even with a recap, it's the selenium giving up the ghost. Since the plate is off on the FM tube when on AM, I assume the extra draw on FM zaps the selenium. Sometimes I wish they had just used a rectifier tube!
On some sets the 12BE6 is your AM tube if I recall right.
No matter where you go, there you are.
(This post was last modified: 08-18-2024, 05:31 PM by
Jayce.)