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 Schematic needed AWA EFCO usl 46
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 Return to top of page · Post #: 16 · Written at 9:41:31 AM on 15 May 2016.
TV Collector's Gravatar
 Location: Ballarat, VIC
 Member since 4 January 2011
 Member #: 803
 Postcount: 456

This chassis has a home built look to it.

The gooey waxed paper caps are well beyond their useful life. None are any good these days, they all have leakage resistance which shows up best when tested with 100v or more. The average multimeter test is only applying a few volts which is not enough to show how bad the caps are.

Do check all the resistors as well while you are at it. They can often drift well beyond the tolerance of the stated value.

 Return to top of page · Post #: 17 · Written at 4:43:24 PM on 15 May 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3865

Would agree with wax paper cap comment; I rarely bother to test them & that's normally around 500VDC if I do. 200Meg is bottom for a coupling cap & I have not found a wax paper that good.

At least the amplifier circuit is nothing unusual, in that it is a fairly common layout. It can be reverse engineered from the link Brad posted into my last comment.


 Return to top of page · Post #: 18 · Written at 8:45:48 AM on 15 October 2016.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1349

Regards the dial markings:

EFCO made radio dials and other similar components for radio manufacturers who were too small to make their own. Also window and door hardware, maybe even still today?

The "AWA" refers to the tuning gang, the dial markings are designed to match an AWA gang. And yes, that is an AWA part. The multi-band coil and switch module may be Jabel.

The radio brand? A small volume manufacturer. But an impressive radio and amplifier. Might be a Radio and Hobbies design?
Doesn't look like AW Jackson (Precedent), wiring is too untidy. Might be KG Harris (Calstan). Early '50s.

Rectifier - 5U4
Outputs - 6L6 is a good guess. Maybe KT88? Too early for 6CA7. All would work......

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