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Success Stories If you have successfully repaired or restored a piece of equipment, why not write up what you did and post details here. Particularly if it was interesting, unusual or challenging. PLEASE DO NOT POST REQUESTS FOR HELP HERE! |
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29th Jan 2009, 11:50 pm | #1 |
Nonode
Join Date: May 2005
Location: Godalming, Surrey, UK.
Posts: 2,593
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1956 Stella ST106A AC mains MW/LW/SW 5 valve table radio
Hello again,
Here's a good looking bakelite cased radio from the mid 1950s. The case of the Stella ST106A is the same as that of the earlier Mullard MAS244 MW/SW set (which has an additional EM34 magic eye), and its chassis the same as that in the Philips 341A. I built this set from two, a cheap one from eBay which didn't work and its case was scruffy, and a second not so cheap set from PastTimes radio and that didn't work either, its dial cord broken, its mains transformer was found to be leaking quite badly, but its case was in good condition. I dismantled both sets, and it's a fiddly job to get the chassis out of these cos the pointer is tucked up into the front compartment of the case and one also needs to remove the two dial lamps screwed onto the front underside of the case. I selected the case from the PastTimes set but as its transformer was knackered and I didn't fancy fitting a new cord, I used the chassis from the other one plus the best cosmetic parts from both sets. Two sets of service data sheets are available for this model from Paul Stenning's site above, Trader sheet 1070 covering the Philips 310A (which is not quite the same as these ST106As which both have an ECH81 fitted in place of the ECH42 plus other minor differences), and three pages for the Stella ST106A from R & TVS which matched both these sets so I chose to work from that one. I replaced the mains lead with new 3 core cable and also the audio coupling capacitor, cleaned the volume pot, tone pot, waveband switch and all the valve pins and bases with Servisol 10, switched it on and .... still nothing. I checked the voltage from the EZ40 rectifier and that was fine and touching the coupling cap lead with a screwdriver caused a hum so the amp was OK so I swapped in spare ECH81, EAF42 and EBC41 valves but still nothing. I rocked the valves around on their bases one by one to ensure good contact and rocking the EAF42 caused an intermittant signal, so I checked the base from underneath and discovered that one of the tags in the base was broken as half of it came straight off. There were two unused tags in the EL41 base so I pinched one of those, replaced the broken one, soldered the wires back onto it, switched on and away she went, SW was working well but both MW and LW were quiet. I then proceeded to replace the rest of the black pitch capacitors and some of them are long obsolete values in the UK, ie: 1800pf, 2700pf, 6800pf, 8200pf ,12000pf and 15000pf, but I managed to get new high voltage replacements with original capacitance values, "orange dips" from Justradios in Canada. I checked the old capacitors as I was replacing them and one or two were still OK and not leaky, so I left the one on the output transformer in place, a big black pitch 6800pf 1000v cap, as it tested good. Finally as I had several brand new Mullard EL41s which I'd bought at Tonbridge for 70p each, I treated the Stella to one as the old one was looking rather black inside. I took the set over to Ron Bryan check it over and to re-align. When attempts were made to turn the MW and LW RF trimmers with a small screwdriver, the whole cores sank downwards into the cans so adjustment was achieved by pulling the adjusters up and down with long-nosed pliers .... they stayed put afterwards though and both MW and LW peaked up well. The case was relatively straightforward to restore, just a clean inside and out with white spirit and then a polish with Brasso and the pieces of paper which secure the foil aerial to the inside of the case were stuck back on. The only paint peeling was that on the two left-hand knobs so I repainted those with Ivory acrylic paint. Sadly the grille cloth on both sets was worn and stained so I couldn't do much about that, other than a light clean with a paintbrush. The Stella ST106A (and Mullard MAS244) is IMHO a very attractive design, and much more interesting than the alternative Philips models. This one works very well now on all wavebands, picking up everything on MW and LW and loads of stations on SW with just its internal aerial, and it sounds good too. Its case is in very good condition too apart from its scruffy grille cloth, so I have placed an order with Corrien Maas to weave me some new material for it .... I think it's well worth doing ! Howard |
30th Jan 2009, 12:10 am | #2 |
Dekatron
Join Date: Sep 2003
Location: Bolton, Greater Manchester, UK.
Posts: 6,644
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Re: 1956 Stella ST106A AC mains MW/LW/SW 5 valve table radio
Nice set, and given the Howard treatment too! I fully understand the problem of restringing and with the mains transformer having got a bit hot, you were wise to leave that chassis alone!
They are nice sets, you're right. Cheers, Steve P.
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If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...? |
30th Jan 2009, 9:18 am | #3 |
Nonode
Join Date: May 2006
Location: St Albans, Herts, UK.
Posts: 2,193
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Re: 1956 Stella ST106A AC mains MW/LW/SW 5 valve table radio
That's a nice job Howard. Well done that man!
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All the very best, Tas |
30th Jan 2009, 5:16 pm | #4 |
Retired Dormant Member
Join Date: Jun 2003
Location: Scunthorpe, UK
Posts: 154
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Re: 1956 Stella ST106A AC mains MW/LW/SW 5 valve table radio
Another good one Howard! I have restored 2 ST102's with both types of frequency changers.
Incidentally does "Corrien Maas" referred to in your post do grill cloth for anyone? I have only dealt with Ben Djikman. John |
31st Jan 2009, 3:29 pm | #5 |
Nonode
Join Date: May 2005
Location: Godalming, Surrey, UK.
Posts: 2,593
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Re: 1956 Stella ST106A AC mains MW/LW/SW 5 valve table radio
Hello John,
Yes she will attempt to remake any loudspeaker cloth for anyone. She keeps some cloths in stock, mainly for Dutch & German sets, but also for the round Ekco sets. https://www.vintage-radio.net/forum/...ad.php?t=36407 Howard |
2nd Feb 2009, 4:40 pm | #6 |
Dekatron
Join Date: Jan 2003
Location: Bradford on Avon, Wiltshire, UK.
Posts: 3,310
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Re: 1956 Stella ST106A AC mains MW/LW/SW 5 valve table radio
Another splendid job Howard!
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"Nothing is as dangerous as being too modern;one is apt to grow old fashioned quite suddenly." |
3rd Feb 2009, 3:19 pm | #7 |
Retired Dormant Member
Join Date: Jun 2003
Location: Scunthorpe, UK
Posts: 154
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Re: 1956 Stella ST106A AC mains MW/LW/SW 5 valve table radio
Howard, missed the thread about Corrien Maas. Many thanks.
John. |