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There is a set available, regular thing, hum, etc,etc. Cabinet appears to be easily restored. I think I can get it for less than $200.00.Do not know much about those sets. Opinions?
Thanks in advance.
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The AK 84 was their first cathedral style radio, and while not as ornate as later offerings such as the model 82, it is still considered a beautiful cabinet.
Price is dependent on condition of chassis and cabinet, and I'm not sure what you consider "easily restored", but in decent shape under $200 sounds like a very good price.
I would not plug it in again until, at the least, the filter capacitors are replaced, or that hum may turn into a transformer smoking. Good luck, the AK 84 is a very nice radio and one of my favorites.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
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Agree, a model 84 in decent shape is worth 200.00
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If it is in decent shape.....I have not seen any below 300 on eBay and in Kutztown they were $350 the lowest; none sold though but the owners do stick by the price and won't budge.
So....yes, below $200 seems like a good deal.
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Which manufacturer supplied tubes for AK 84? I have some 24 and 27 but they are Philco.
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I think they usually used Cunningham tubes, but that probably would not have been an absolute rule.
John KK4ZLF
Lexington, KY
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I had heard that AK used both RCA and Cunningham. Same tubes.
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One thing to watch for on some of the A.K cathedrals are bad power transformers, I can't remember whether a model 84 is one of them or not. With luck the one in this set may have been replaced, rewound, or may be a 25 cycle one.
Regards
Arran
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If I have an original weak globe RCA 80 and instead of paying for the single tube almost 1/3 of the radio price went with a full wave diode rectifier under the chassis (keeping the tube as a decorative, lit filament piece, of course), which diodes(##) are most suitable for an application?
That is if someone have already done so. Thanks.
(This post was last modified: 05-27-2014, 09:40 AM by fields 100.)
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I would not recommend it. First, the diodes have a very low forward drop, so unless you add series resistors you will end up with high B+ voltage. The tube 80 also acts as sort of a fuse, in that under momentary overload it will limit the transformer current to a safer value than a silicon diode. With a short on the B+ line the plates of the 80 may glow red, but if shut off quickly, likely no damage will result.
How bad is your 80? Sometimes a weak 80 still has enough emission to provide rated B+ voltage to the radio, especially with today's higher line voltage
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Personally I wouldn't bother doing that with a tube as readily available as an 80. You can get a new 80 for $12 or good used for $6:
https://docs.google.com/spreadsheet/ccc?...0foD#gid=4
It won't be a globe but it won't require kludging in diodes and resistors under the chassis either. Keep your eyes open and you'll eventually find a good globe 80 on eBay, a radio meet, an old parts set, or a wanted ad. There is no shortage of globe 80's out there if you're patient.
I'd also measure B+ with a good 80 and then your weak one; often a weak 80 isn't that far off, depending on the parameters of the tube tester used.
If you're still determined you can use two 1N4007's and a wire wound resistor to drop the B+ down to what it measures with a known good 80 in the circuit.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
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It is in the yellow field, about 55-56.I have not tried it yet on this radio. So, if the B+ within a spec.,I can use it, right?
But the diodes are definitely out. Hiding tiny diodes is one thing, but the wire resistor...
Thanks, guys.
(This post was last modified: 05-27-2014, 12:25 PM by fields 100.)
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Yes, it should be fine if the B+ is OK. Just make sure you change out the filter and paper capacitors before firing it up.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
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