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 How to Identify this set.
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 Return to top of page · Post #: 1 · Written at 8:25:10 PM on 16 May 2016.
Kakadumh's Gravatar
 Location: Darlington, WA
 Member since 30 March 2016
 Member #: 1897
 Postcount: 146

Another mate has dropped onto my bench a 5 valve dual wave set that has seen far better days.

No brand name on the cabinet that we can decipher, nothing on the dial face which is unsual in that the dial face is attached to the cabinet & NOT the set it self.

Mounted where it is behind the dial glass on the set itself is a little lever which is attached to the band change switch which moves a placard up & down upon which is labelled B.Cast & S.Wave.

Valves identified so far are 5Y3, 6V6 & EK2G...the other 2 labels are gone so no idea at all.

On the rear of the set is stamped EJSA & below is obviously what is a serial number.

Any clues in that lot to try & indentify & get hold of a circuit to get this beast going...has the quite old Brown cardboard covered Ducon electro caps & all paper caps are Chanex.
Also uses a 10" Rola Electro Dynamic speaker. It is a quite well made set with neat wiring and the maker actually had spray painted the underside of the chassis.

If a photo of 2 would help can do so.
Update ...Brad has uploaded some photos, thanks. I simply HAD to include that one with the bare twisted earthing wire wound around the paper caps to hold them in place. Never seen that before but as it appears this chassis was built to supply retailers so they could use their own brand names it makes sense to secure the caps like that to handle the rigours back then of transport from east coast to west coast. Otherwise things could flop about & end up creating broken joints or worse still hairy intermittents. I could tell you about some nasty ones in telephone switching gear created by wire off cuts.
The other interesting thing about this chassis is those flat metal earthing straps run around the chassis which is something else I have never encountered.

Lindsay

Unknown Radio
Unknown Radio
Unknown Radio
Unknown Radio


 
 Return to top of page · Post #: 2 · Written at 9:17:23 PM on 16 May 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5830

Likely Croyden model EJSA of 1940, a console set, original line-up 6J8G, 6U7G, 6B6G, 6F6G, 5Y3G.

There are many Philips and Mullard sets of that vintage with line up: EK2G, 6U7G, 6B6G, 6V6G, 5Y3.


 
 Return to top of page · Post #: 3 · Written at 10:19:24 PM on 16 May 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4178

Breville 730 had a flag like that, but EK2G is possibly wrong for a later SW. I would expect ECH35 or ECH33 Triode Hexode in a SW, not an Octode from 1938 onward?

http://www.siliconchip.com.au/Issue/2012/May/Breville+730+dual-wave+5-valve+receiver+


 
 Return to top of page · Post #: 4 · Written at 10:27:23 PM on 16 May 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5830

I gather the Breville 730 has a permanent magnet speaker. I take it the OP's set has an electrodynamic one.

I've not encountered that band switch feature before.


 
 Return to top of page · Post #: 5 · Written at 9:32:33 AM on 17 May 2016.
Kakadumh's Gravatar
 Location: Darlington, WA
 Member since 30 March 2016
 Member #: 1897
 Postcount: 146

Thanks for the info...will do some digging.

With sets like this that have been lurking in sheds etc people unknowingly move valves around & I have seen even swap them between sets thinking somehow they can "fix" things...but often not.

Lindsay


 
 Return to top of page · Post #: 6 · Written at 4:28:26 PM on 17 May 2016.
Kakadumh's Gravatar
 Location: Darlington, WA
 Member since 30 March 2016
 Member #: 1897
 Postcount: 146

Some further info.

Got hold of the dial glass and in a VERY fancy script type lettering is the name Airlord...Absolutely NO markings on the cabinet.

Cannot turn up any circuits of other info re the name Croyden... where might I find those??

Lindsay


 
 Return to top of page · Post #: 7 · Written at 5:15:06 PM on 17 May 2016.
MonochromeTV's avatar
 Location: Melbourne, VIC
 Member since 20 September 2011
 Member #: 1009
 Postcount: 1098

Interesting.

Airlord is the generic housebrand for Boan's, a Perth retailer.

Don't rule out the Croyden, or rather the Eclipse ESJA chassis just yet. Eclipse chassis' were often used in generic house brand radio's and it is quite possible the Airlord used them as well.

The Croyden ESJA schematic can be found in volume 4 of the AORSM.

A photo would quickly determine if this is a Eclipse chassis.


 
 Return to top of page · Post #: 8 · Written at 5:51:03 PM on 17 May 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5830

Cannot turn up any circuits of other info re the name Croyden ... where might I find those??

I have emailed you the EJSA schematic.


 
 Return to top of page · Post #: 9 · Written at 6:22:08 PM on 17 May 2016.
Kakadumh's Gravatar
 Location: Darlington, WA
 Member since 30 March 2016
 Member #: 1897
 Postcount: 146

Monochrome TV,

Boans certainly were a WA supplier but long since gone of course..Airlord rang a bell but I could not recall from just where. Makes a bit more sense now.

GTC,

That circuit is just what the doctor ordered...many thanks & in the meantime had confirmed that one of the unmarked valves is a 6U7 sitting exactly where it should be as per the circuit. A 6V6 had been substituted for the 6F6.
So now I can get to work getting it running & back into the cabinet once the mate cleans that up.

Great forum this.

Lindsay


 
 Return to top of page · Post #: 10 · Written at 8:26:07 PM on 18 May 2016.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 6174

Photos uploaded.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 11 · Written at 10:34:59 PM on 18 May 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1303

Nice radio, hopefully it will restore well, after replacement of those 12 paper & electrolytic caps (Chanex and Ducon).

EK2G appears to be pin-compatible with 6J8G, ECH33 et al.

Haven't seen a band-switch label quite like that one.


 
 Return to top of page · Post #: 12 · Written at 10:35:21 PM on 18 May 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4178

Now that we see photos things are different. Flag is not the same mechanism as Breville; It used a cable. Its 1948 & has a 6"permag speaker and is a table type in wood.

6V6 will be likely held back by the 6F6 bias which is greater, possibly good as 6V6 is capable of more current draw.

A circuit clue... it is not common to see both a top trimmer & slug tuned IF in the same set?

Chanex were not used by a lot of manufacturers, and I have serviced a radio recently with them in it.

There is a number on the transformer, that may appear in a parts list.

Marc


 
 Return to top of page · Post #: 13 · Written at 7:52:19 AM on 19 May 2016.
MonochromeTV's avatar
 Location: Melbourne, VIC
 Member since 20 September 2011
 Member #: 1009
 Postcount: 1098

The power transformer has a Astor/Radio Corp part number on it (PT262). I have no Astor information going that far back regarding part numbers to confirm it. I still think it is most likely an Eclipse chassis. By 1940 Eclipse Radio was fully under the Electronics Industries (Astor) umbrella.

One thing regarding the power transformer is that the electricity supply in metropolitan Perth back in 1940 was 250 volts, 40 cycles (hertz). Something that may need to be checked out.


 
 Return to top of page · Post #: 14 · Written at 9:29:58 AM on 19 May 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4178

Transformer: A step in elimination. Now what Astor / Eclipse has a first IF top trimmer & a slug tuned 2nd IFT? Astor, by the era this seems to be falling into, were using 6J8 in SW sets; 6J8 having come into circulation 2/38.

Marc


 
 Return to top of page · Post #: 15 · Written at 11:34:03 AM on 19 May 2016.
Kakadumh's Gravatar
 Location: Darlington, WA
 Member since 30 March 2016
 Member #: 1897
 Postcount: 146

The circuit appears to be spot on from what I can discern after a few quick checks around a couple of the valves. So I guess that does date it rather well.

As to the 40hz/50hz situation in WA in the 1940's I can recall the switchover that was done in our suburb in 1947 & the main concern was with fridges or anything much with motors & the supply authority went around whacking in what I think were small auto transfomers in the power cords of anything that might be at risk but I cannot recall just what transpired AFTER the switchover.

We did have our grandmothers big old console radio in the house at the time & it did not get a trannie at all. It had come from a rural 40hz area & remained working for many years after on the 50hz supply at our home.

I rather doubt that there was any real need for those auto trannies anyway as years later whilst I was working at Exmouth our radio TX (ISB) site was setup for 60hz operation as the PMG plan at that time was to take AC supply from the US Navy power system. It never eventuated due to the cost of underground power so we ran our own 35 kva diesels (one On one Off weekly) until the site was closed some 10 years later. In all that time the AWA 5 Kw ATH5 transmitter which was a 50Hz plant ran no worries and any air con units that died we had rejigged with off the shelf available WA 50Hz compressors instead of waiting for imported 60Hz sods from USA at huge expense. Our refrigeration contractor said at the time that the 50Hz units ran more efficiently on 60Hz & even the US Navy themselves were doing the same thing rather than waiting ages for supply via navy channels ex USA.

Now to start cleaning some of the surface rust off that chassis top face under that layer of grime...it IS quite rusty on top. I think a bit of a clean off with kero & then a light coat of Penetrol Rust coater maybe the simplest answer to preserve it.

Thanks for all comments most helpful.

Lindsay

Edit: Further developments. After cleaning all the years of gunk & mouse dirt off the top of the chassis reveals a stamped in the metal label of EK2G alongside where that valve was plugged in. No other valve types are marked. Possibly a valve change during production if the 6J8G supplies had dried up due to WWII demands on supplies as noted in other posts. That changes things somewhat as the 6J8G is a Triode Heptode tube & the EK2G is simply an Octode
At first glance the wiring around the EK2G bears no resemblance to the published circuit using a 6J8G.
So when the thing dries off & I start further poking about an amended circuit for that section seems to be the next step.
Fixing these old girls certainly taxes the old grey matter.


 
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