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All, Started to work on a RCA Victrola V-210 . Here is a picture of front..
[Image: http://i292.photobucket.com/albums/mm38/...mizrhk.jpg]
Here is bottom..
[Image: http://i292.photobucket.com/albums/mm38/...mfn1jo.jpg]
Anyone have a Clue to what this is?
[Image: http://i292.photobucket.com/albums/mm38/...vcghcg.jpg]
I think its a Cap But never seen anything like it before..
This has a lot of brittle wires in it. So a lot will have to be changed..
More to follow..
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Ok, Next problem.. 2 Dogbone resistors.. Wattage? they are about 2 in long and about 1/2 in thick...
[Image: http://i292.photobucket.com/albums/mm38/...gdnaz6.jpg]
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Yup That helps a lot..
Thanks
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Ok, Update Still waiting on caps for replacement. Had to order some .0035 uf 1600 volt ones.
and a Electrolitic can from Play things of the past..
So radio is on hold until I get parts in..
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Looks like it is coming along...
Those 1600V caps are a pain... I see a few in one of my kutztown radios and know I will have to make an order just to get them... grrrrrr.....
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You could serialize 3 caps of 0.01uF 630V and get thee the one you need.
I have not seen the sch (a link would help as always), but the WV might not even be necessary.......
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Its the C35 and C36 both .0035 on output tubes..
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Those capacitors, C35 and C36, are between the plate of each 6K6 power output tube and ground. The maximum power output of the amplifier is only rated at 5.5 Watts with 220 volts on the plates so they are not exactly overdriving the 6K6s to start with so maybe they used 1600 Volt caps because they wanted .0035 uf caps and got a deal on some 1.6 KV ones, or already had them in stock and didn't want to order lower voltage ones. If those two capacitors were connected between the center tap of the output transformer and the two plates, or were connected between one 6K6 plate to the other 6K6 plate across the transformer primary then I would say that 1600 VDC caps would be needed but I think that you might be able to get away with using a pair of 630 Volt rated caps in this case.
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Arran
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One could often see 1.5kV caps in this exact place in both Class A or Class AB amps.
It is possible that at this capacitance the caps just can easily be bought with this WV rating, but also if the load gets disconnected while the amp is working actively the voltage across the primary can reach some large number and this, as I heard, is one of the reason for the large WV rating.
This last one would make sense where the load (speaker) is plugged and can be accidentally disconnected. If the speaker is hardwired, there is no need in anything above 500V.
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Thanks for the info.. My order for caps just arrived so I have no problem replacing with the proper voltage..
I will know next time I see something like this in-case I do not have the right voltage...
Thanks again for the help.
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(09-23-2016, 08:20 AM)morzh Wrote: One could often see 1.5kV caps in this exact place in both Class A or Class AB amps.
It is possible that at this capacitance the caps just can easily be bought with this WV rating, but also if the load gets disconnected while the amp is working actively the voltage across the primary can reach some large number and this, as I heard, is one of the reason for the large WV rating.
This last one would make sense where the load (speaker) is plugged and can be accidentally disconnected. If the speaker is hardwired, there is no need in anything above 500V.
Mike;
On RCA console sets from this period they were still using electrodynamic speakers, so if the speaker were accidentally disconnected there would be no B+ voltage for either the plates nor the screen grids. I'm not sure about U.S RCA sets but the Canadian built ones had a plug mounted on the back of the speaker basket that mated up with a socket on the end of the speaker cable, and the output transformer was normally mounted on the speaker so the cable would need at least four wires in a set like this, all of which had B+ running through them.
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Arran
I mean, when the very fact of the disconnect occurs, there are possible spikes across the output transformer due to particular sequence of plug disconnect.
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Ok now that I got my tube tester working correctly while waiting on parts for this Its time to start on it again.. The resistors I need are due on Monday.. I will start to recap first .. Got a new electrolytic can and will install tomorrow. Then on to rest of the Caps..
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