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 Electrosound V53 Radiogram
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 Return to top of page · Post #: 1 · Written at 7:13:03 PM on 20 May 2020.
Viccadillac's Gravatar
 Location: Perth, WA
 Member since 7 May 2012
 Member #: 1140
 Postcount: 152

Hello members,

Either I am getting old and missing things, but I was hoping someone may have schematics and relative info on the Electrosound V53 chassis used in the radiogram.

The unit is 32volt and has a plug in vibrator power supply. The transformer is open so I either find, rewind or make a new power supply .

It Has a strange valve line up 6N8 , 6AN7, 6N8 ,6N8 , 6V6. Or someone has played with it.

If the transformer was ok I guess I would recap and run It off 32v . Any help greatly appreciated.

Regards
Vic


 
 Return to top of page · Post #: 2 · Written at 10:03:35 PM on 20 May 2020.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6012

From what I can see in my data, there have been a few versions of the 5 valve 32V DC vibrator T/W between 1948 and 1954.

The 1950 version is given as 6SK7GT 6AN7 6SK7GT 6SQ7GT 6V6GT

I have emailed you the 1954 version schematic in case that is of some use.


 
 Return to top of page · Post #: 3 · Written at 2:38:40 PM on 21 May 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4344

I can go with that combination as liable to work even 6N8 has diode plates. One 6N8 TRF amp V1, 6AN7 (V2) is a Pentagrid with triode exciter; Next N8 will be the IF and the other det / 1st audio & 6V6 audio OP. There is 32V stuff buried here somewhere?

I did send a 32V STC set home in the last few weeks. I noted it had a polarised cap on the supply side and added a diode to save its life.

The other alternative is to fit a conventional transformer for mains.

Marc


 
 Return to top of page · Post #: 4 · Written at 6:41:46 PM on 21 May 2020.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1380

It Has a strange valve line up 6N8 , 6AN7, 6N8 ,6N8 , 6V6.


It's a workable lineup.

6N8 - RF amp
6AN7 - mixer & local osc
6N8 - IF amp
6N8 - AF amp
6V6 - AF output.

The detector will be on either the 2nd or 3rd 6N8.

But of course you should check, just in case someone really has played around.


 
 Return to top of page · Post #: 5 · Written at 2:19:38 AM on 23 May 2020.
Viccadillac's Gravatar
 Location: Perth, WA
 Member since 7 May 2012
 Member #: 1140
 Postcount: 152

Thanks for the reply guys.

Looks like I will have to configure a standard mains transformer setup . Seems everything I do is not straight forward. But it exercise the brain matter.

Cheers
Vic


 
 Return to top of page · Post #: 6 · Written at 7:51:11 AM on 23 May 2020.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 882

Hey Vic!

"configure a standard mains transformer"

That is an approach that does work.
Just grab a modern bobbin wound mains tranny of the wattage size required, leave the 240 primary winding as is and "reconfigure" the secondary winding to arrive at 30 volt or so DC after the rectifier and filter pack.

If you are really lucky you may find some transistor amp/radio tranny with a 20 to 30 volt secondary already on it, that would put you in the ball park as is.
A 240/115 stepdown would be a chance as well, strip the 115 off and re-use the wire but cut into 4 parallel strands, wind that back on, give 115/4 = 30 volt or so.
Some junk solder iron control boxes have about 25 volt AC secondarys.

If you have winding wire on hand the job is easier, just work out the turns per volt (count the turns as you strip off and you know the volts) then wind back on your choice of gauge and number to get the volts you want.
Most Jaycar style trannys and radio types are pretty slack on varnish and pull apart very easily.
Other types need a bit more energy to pull apart.
Jaycars oppositon in WA Altronics may have a cat part as well.

A standard full wave rectifier with a choke/capacitor filter should reduce the ripple, just thinking if there are no direct heat filmant valves then a bit of ripple may not be a problem and you may get away with just capacitor and no choke filtering.


Ideas.

Fred.


 
 Return to top of page · Post #: 7 · Written at 9:46:13 PM on 23 May 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4344

There was more than one radio made with a more or less, plug in module where the same line up could be 32V or 240V dependant only on the PSU used.

The STC has series heaters with originally 39 Ohm resistors across the heaters. I used 40 but the series diode would lose nearly a volt anyway. One could also rewire the heaters to parallel, & use a diode rectifier, on a conventional transformer.

Marc


 
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