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-   -   Emerson Big Miracle (https://www.vintage-radio.net/forum/showthread.php?t=147484)

PJL 17th Jun 2018 10:32 pm

Emerson Big Miracle
 
3 Attachment(s)
Unfinished projects take up so much more space, cabinet, chassis, bag of bits that were taken off, back, jiffy bag of valves. So, from now on I am not going to start a new project until the last is finished. So here it is before restoration.

PJL 17th Jun 2018 10:49 pm

Re: Emerson Big Miracle
 
3 Attachment(s)
Cleaned up chassis. Restuffed capacitors as they were all very leaky. Piggy backed resistors to correct the 100-300% value drift. Made up a fake dual electrolytic and a missing tone correction capacitor. replaced a 6D6 with the correct 6C6. T-cut the cabinet and celluloid window

To maximise gain this set uses very high anode loads and screen feed resistors so any leakage will kill it. Not knowing what was original I have restuffed some late 40's replacements and the electrolytic, modelled after a pic on the internet, was also probably a replacement.

It works OK but I am getting a painful amount of fading on MW at the moment and of course there is no AGC on this simple TRF. Talk of over driving components, the service sheet indicates the rectifier has 126V on the cathode and the electrolytic is specified as 100V (just as well I went for a 160V part).

The knobs are wrong and I should make up some that look more like the originals but I will allow myself to move on to another project!

Tractionist 18th Jun 2018 7:55 am

Re: Emerson Big Miracle
 
Well done! Nice and sympathetic ...... and now all in one place [hopefully 'pride of place']!!

Having now acquainted yourself with this set - it's always good to take a little breather in order to get your head around those 'finishing touches' in a leisurely, thoughtful and measured way. Who knows - the forum may yet yield the correct knobs?

Nice work PJ [P.S. A main to chassis lead grommet and restraint clip?].

Nickthedentist 18th Jun 2018 7:55 am

Re: Emerson Big Miracle
 
Very nice work, that looks lovely inside and out.

Quote:

Originally Posted by PJL (Post 1052592)
Unfinished projects take up so much more space, cabinet, chassis, bag of bits that were taken off, back, jiffy bag of valves. So, from now on I am not going to start a new project until the last is finished. So here it is before restoration.

What a sensible sentiment. I'm trying to do the same, both with radios and clocks, but am failing somewhat :-/

N.

Andrew2 18th Jun 2018 8:44 am

Re: Emerson Big Miracle
 
My word, that's come up nice! Re the AGC, it's amazing just how much we rely on AGC when tuning around the bands, and we don't realise just how hard it's working to keep the output level constant. My 'posh' R&S EB150 receiver has a manual gain facility and the MW band becomes a tangle of silences and wild distortion if I use it. The knob-twiddling required to keep everything in line is manic!

PJL 18th Jun 2018 12:51 pm

Re: Emerson Big Miracle
 
Thanks for the nice words.

The mains cable is not as bad as it looks as there is a metal grommet fitted in the chassis but it does need something done about retention.

The dial lamp is set above the dial in a shallow half circle recess in the cabinet. As the catalin is opaque, all that happens is that area of the cabinet glows bright yellow making the dial even less visible. I do wonder if it is supposed to have a silver paper lining to the recess.

The knobs are apparently made from the same plastic as the speaker fret and rarely survive. They should be a bullet style. I might one day fabricate some and spray with black paint.

It came with a homemade ply back but the screw holes have been filled with padding and I think wood screws used (at least there was one in it).

It also came with a line dropper adaptor cable for 240V. It is in reasonable condition but I am not using it and have sealed it in a plastic bag as it probably contains asbestos.

This is another one of those cost saving AC/DC sets where a single pole on/off switch disconnects the mains from chassis. Depending on how you insert the plug, you either get electrocuted when the set is on or when its off. There is minimal attempt to prevent touching parts that are connected to chassis so I guess many of these sets would have been wrecked when the user received a shock and involuntarily sent the set flying across the room.

Lloyd 1985 18th Jun 2018 4:50 pm

Re: Emerson Big Miracle
 
Lovely looking radio, amazing how well the cabinet came up! I actually thought that it was supposed to be that orange colour until you put the picture of it all cleaned up on!

Also know what you mean about projects taking up so much room, I have been working on an Ekco RS3 for the last 6 months, and whilst it was in bits it was taking up most of the room in the workshop.

Regards
Lloyd


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