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-   -   Ace Embassy 50 (https://www.vintage-radio.net/forum/showthread.php?t=157346)

gary_crutchley 16th Jun 2019 5:28 pm

Ace Embassy 50
 
4 Attachment(s)
Hi all,

I have recently been given an Ace Embassy 50 radio. I can't find any specific service data for this set, but the chassis looks very similar to the circuit for the 357S or 3561S diagram that I purchased from Paul's site. The image "Model" shows the set details attached to the chassis.

I have removed the chassis to have a look at the condition of the components underneath. As a result I have a couple of questions, if anyone can help me please.

Firstly after removing the chassis, a black wire has parted company with its original connection point. It clearly wasn't well soldered, but I'm unsure where it connects, you can see it on the left in "Image 1". It appears to go to the on/off tone switch. It originates at a junction between UU12 valve and the 32+32+8uF electrolytic, which can be seen in "Image 2", it goes through the rubber grommet. Can anyone help me to understand where it should connect please, and what it's purpose is?

Secondly, I noticed that one of the caps is deeply cracked and needs to be changed, see image "Cap". The brand appears to be "WIMA"? This particular 3300pF cap connects to the EABC80. However, there are several others of the same type. These show surface crazing of the brown glaze, but no cracks. Should I replace them all?

Many thanks in advance.

Regards,

Gary

Graham G3ZVT 16th Jun 2019 5:52 pm

Re: Ace Embassy 50
 
Wima capacitors have, shall we say, a reputation. Change them on sight.

CambridgeWorks 16th Jun 2019 7:32 pm

Re: Ace Embassy 50
 
Yes, even back in 1967 when I worked for "Modern Television" in Peterborough they were a blanket replacement in Grundig tape recorders. Fitted Mullard "Mustards" replacements IIRC.
Rob

gary_crutchley 16th Jun 2019 7:55 pm

Re: Ace Embassy 50
 
Quote:

Originally Posted by rambo1152 (Post 1153165)
Wima capacitors have, shall we say, a reputation. Change them on sight.

Quote:

Originally Posted by robinshack (Post 1153187)
Yes, even back in 1967 when I worked for "Modern Television" in Peterborough they were a blanket replacement in Grundig tape recorders. Fitted Mullard "Mustards" replacements IIRC.
Rob

Thanks both, that's very helpful. The set does actually function surprisingly, I tried it on my lamp limiter.

Can anyone advise on the disconnected wire that I mentioned please?

Gary

ms660 16th Jun 2019 8:34 pm

Re: Ace Embassy 50
 
That part of the layout in the photo's looks very similar to the layout shown in the Ace Crescendo service sheet (Trader)

If one end of that disconnected black wire is connected to chassis it's possible that the disconnected end might have been soldered to the body of the tone pot, it looks as though the bottom end resistor in the tone circuit (connected to the right hand tag of the pot in the 2nd photo) might also be soldered to the pots body?

Lawrence.

gary_crutchley 16th Jun 2019 9:26 pm

Re: Ace Embassy 50
 
Thanks Lawrence, I'll take another look. It does appear that the underside connection is to a chassis tag. I thought the wire had disconnected when I took the chassis out, but looking again at the photo I think it may have been off for a while. I presume the set would still work if this ground was disconnected?

ms660 16th Jun 2019 9:57 pm

Re: Ace Embassy 50
 
Quote:

Originally Posted by gary_crutchley (Post 1153216)
I presume the set would still work if this ground was disconnected?

In the scenario I suggested and going by the Crescendo schematic, yes the receiver would work ok but only if the tone pots body had continuity with the chassis via its fixing nut etc otherwise g1 of the output valve would be floating which would mean the output valve would be operating with no bias.

Lawrence.

gary_crutchley 16th Jun 2019 10:31 pm

Re: Ace Embassy 50
 
Thanks Lawrence.


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