Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
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..
Skip...
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
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]
Skip...
Posts: 5,088
Threads: 270
Joined: Nov 2012
City: Wilsonville
State, Province, Country: OR
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Yup That helps a lot..
Thanks
Skip...
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
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..
Skip...
Posts: 4,109
Threads: 310
Joined: Nov 2013
City: Kings Park NY
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.....
Times I have been electrocuted in 2021
As of 1/01/2021
AC: 4 DC: 1
Last year: 6
Posts: 15,825
Threads: 554
Joined: Oct 2011
City: Jackson, NJ
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.
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Its the C35 and C36 both .0035 on output tubes..
Skip...
Posts: 4,707
Threads: 51
Joined: Sep 2008
City: Sandwick, BC, CA
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.
Regards
Arran
Posts: 15,825
Threads: 554
Joined: Oct 2011
City: Jackson, NJ
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.
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.
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
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.
Skip...
Posts: 4,707
Threads: 51
Joined: Sep 2008
City: Sandwick, BC, CA
(09-23-2016, 09:20 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.
Regards
Arran
Posts: 15,825
Threads: 554
Joined: Oct 2011
City: Jackson, NJ
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.
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.
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
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..
Skip...
Users browsing this thread: 2 Guest(s)
|
|
Recent Posts
|
|
Philco 60 Squealing
|
| I seem to remember eliminating a squeal by changing the IF frequency by a few KHz. Not that you should put too much tru...fenbach — 08:48 PM |
|
Philco 42-390, code 121 speaker
|
| These speakers pop up on eBay regularly, even if at bloated prices.
Honestly, have not seen many parts on swapmeets.morzh — 08:38 PM |
|
Philco 38-7 Speaker
|
| The put-put is not like the speaker problem.morzh — 08:29 PM |
|
Mission Bell Model 19A Car Radio
|
| Hello everyone,
As mentioned in my last post I was going to see if the vibrator / rectifier section could be persuaded...Antipodal — 08:21 PM |
|
Philco 60 Squealing
|
|
Wondering if I did it backwards.
If a coil was wound backwards, the oscillator would not work at all.
Old school...Chas — 07:23 PM |
|
Philco 38-7 Speaker
|
| 4-ohm speaker. Black, Green leads.tludka — 07:00 PM |
|
Philco 42-390, code 121 speaker
|
| #87 on the schematic.
This radio had a 8" Zenith speaker attached to it when I got it. I do don't know the hist...Stevelog — 06:39 PM |
|
Philco 60 Squealing
|
| I'm pretty sure I now have the litz wire soldered. This did not make any difference. Back in April I rewound the seconda...dconant — 06:25 PM |
|
Philco 38-7 Speaker
|
| Just to make sure, you chose either 4 ohm into 5K or into 10K? (blk-org or blk-grn)morzh — 06:23 PM |
|
Philco 38-7 Speaker
|
| I have let this one sit because of other duties. Now I am back, and I have a couple of questions. I hooked up a Hammond ...tludka — 05:34 PM |
|
Who's Online
|
There are currently 4832 online users. [Complete List]
» 1 Member(s) | 4831 Guest(s)
|
|
|
|
 
|
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
