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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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Old 19th May 2018, 12:50 am   #1
martin.m
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Default Ekco A144 repair

This radio has sentimental value as it belonged to my parents. I can remember listening to Alan Freeman's "Pick of the Pops" on it way back in the 1960s. My mother used the Ekco in a spare room until it was taken out of service in the early 2000s.
This model dates from around 1950 and uses a set of "U" series B8A valves with heaters connected in series and fed from a tap on the HT winding of the mains transformer. HT is provided by a UY41 half wave rectifier and the chassis is isolated from the mains.
I removed the chassis from the cabinet and a quick visual inspection revealed that one of the waxy capacitors must have been getting warm and had dripped wax into the bottom of the cabinet. A modern polyester 0.1uF 400v capacitor was fitted and after checking for shorts on the HT supply I switched on. The voltage on the cathode of the UY41 rectifier slowly rose to around 140 volts and moving the meter probe to pin 6 (grid) of the UL41 output valve gave a reading of around 3 volts positive, not a happy state of affairs. Time to switch off.
I had a circuit diagram for this model and, to cut a long story short, changed all the waxy tubular capacitors in the audio circuit (some are hidden on a sub panel) and any that were subject to HT voltage in the rest of the set. Much of the rubber covered wiring on the chassis had to be replaced along with the fabric covered mains flex. The resistors were measured and were found to be within tolerance.
Now on switching on stations could be tuned in, though the controls were crackly and the HT voltage remained at 140 volts. A secondhand UY41 restored this to just over 200 volts and squirts of switch cleaner completed the repair. The sound quality on this model is very good and I am amazed at the improvement in MW and LW reception when using the wire loop aerial built into the set's back cover. Droitwich on 200KHz comes through loud and clear with no electrical interference. Strangely, the lack of HT voltage seemed to make no difference to the sound or reception.
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Old 19th May 2018, 9:36 am   #2
paulsherwin
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Default Re: Ekco A144 repair

These sets are easy to work on and make an excellent first restoration. The loop aerial wrapped around the cardboard back does work surprisingly well, though it is directional so requires the radio to be correctly positioned, which may sometimes be a problem given that it's a big wooden set.

It's my favourite British 50s woodie.
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Old 19th May 2018, 1:05 pm   #3
martin.m
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Default Re: Ekco A144 repair

The radio was bought new from Uptons department store in Middlesbrough around 1952 at a cost of 19. This was equivalent to around 500 in today's money and most people in those days would have bought a new radio on a "Hire Purchase" agreement. Sadly, lovely old radios from this era are worth very little today.
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Old 19th May 2018, 4:25 pm   #4
Phil G4SPZ
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Default Re: Ekco A144 repair

Well done! That's a nice looking set, did you have to do anything to the cabinet?
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Old 19th May 2018, 10:33 pm   #5
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Default Re: Ekco A144 repair

I didn't do anything to the cabinet. Woodworking is not on my list of skills unfortunately. I worked for a TV rental company in the 1970s and our resident "French Polisher" did some repair work on the cabinet front after the veneer behind the control knobs came adrift.
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Old 22nd May 2018, 9:04 pm   #6
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Default Re: Ekco A144 repair

Nice one, Martin.

I find it heartening to hear restoration stories that are linked to someone's heritage or past in a meaningful way.

I'm glad it's up and running and I hope it will give many years of service from now on!
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Old 26th May 2018, 11:43 pm   #7
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Default Re: Ekco A144 repair

Thank you Al.

Sadly, there are not many stations left on MW and LW now. However, I have been playing Internet Radio from my mobile phone connected to the "Gram" socket. Sounds great and I can get any station in the UK!
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Old 15th Aug 2018, 10:34 pm   #8
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Default Re: Ekco A144 repair

Update. The set has been running fine but has suffered from an annoying crackle when turning the volume control, even though the control has been dismantled and cleaned. On this model the grid of the UBC41 audio amp triode is connected directly to the wiper of the control. The valve is biased via a cathode resistor of 4700 Ohms. I don't usually modify vintage circuitry but I tried fitting a 470k resistor from grid to chassis and reconnecting the grid to the control's wiper via a 0.1uF capacitor. Result, a lovely quiet volume control. There was no DC voltage either on the top of the control or the grid of the UBC41 so I'm not quite sure what was going on. I'm going to leave it like that.
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Old 16th Aug 2018, 11:03 am   #9
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Default Re: Ekco A144 repair

I see nothing wrong in adding the components if it enhances the radio's performance.
I am prone to making small improvements myself. It has saved the cost of a new control and there is no knowing if a new pot would not have gone the same way. It takes very little DC current to cause the crackles.

The "missing" grid stopper and coupling capacitor could well have been a cost cutting measure by the makers anyway.

There are those that would disagree, but its your set, its better than it was before, and its your choice.

Sam.
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