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Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc. |
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2nd Jul 2014, 8:23 pm | #1 |
Pentode
Join Date: Mar 2009
Location: Norwich, Norfolk, UK.
Posts: 228
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Ekco CT102
I bought this set many years ago, sold to me as having a duff LOPT and a low emission Mazda CRT swapped from the owners Thorn 2000. I really wanted a Dual standard Hybrid Pye, so bought it and have just been sitting on it. I was recently inspired by a friend who has just restored a similar set by fitting a single standard LOPT.
I started by removing the timebase from the set and stripped it down. The LOPT looked intact with no signs of overheating. All the electrolitic's in the set, including the 4 LT smoother"s at the back of the chassie were leaking a white gunge from them. So i replaced all of them including the blue Philips type. I then left the set on the variac for a day running about 100v HT to reform the HT can. I then powered the set up to full voltage, i had weak sound and an overheating PL509 line output valve. I decided to check for line drive before i totally giving up on the LOPT and there was no drive. Excitement and a glimmer of hope! I had already, as mentioned changed the electrolitiic's, so knew it was not the usual 1 and 4,7uf's in the Oscillator stage, so changed the 390pf Sufflux feedback capacitor. This restored EHT and i had a raster. Well pleased! Next job was to replace more leaking Caps on the "IF" panel, decoader and CDA panel. Low sound was traced to someone replacing the geranium transistor's in the audio module with silicon ones. Luckily i had a spare module to hand. I now had picture and sound, but as expected the CRT was very flat, luckily it responded to being rejuvinated. I could not set the purity, 2 plastic clips had broken on the convergance yoke, so i fitted one from a CT72 which was a direct replacement. A new degaussing blue positor finally resulted in good purity and with the convergance board switched to 405 because the pots were in better condition, good convergance. The cabinet needs attention, so that will be the next job. David |
2nd Jul 2014, 9:06 pm | #2 |
Dekatron
Join Date: Aug 2013
Location: Wigan, Greater Manchester, UK.
Posts: 9,433
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Re: Ekco CT102
There appears to be a small circuit attached to the chassis to the left of the PL509, what is it? I am trying to remember this chassis, we sold a few but it was mainly the single standard one we sold in large numbers.
The tuner is the 6 push button type use in their black and white sets that used to let the centre white tuning knob break away and fly off into the room. You have done a lot of work and it as paid off, the test card looks good. Frank |
2nd Jul 2014, 9:43 pm | #3 |
Octode
Join Date: Jan 2006
Location: Borough of Gateshead, UK.
Posts: 1,420
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Re: Ekco CT102
The results look excellent, well done. Is the LOPT the dual standard one with GY501 EHT rectifier and PD500 shunt stabiliser?
Never had the pleasure in working on one of these early versions. Cheers, Brian |
2nd Jul 2014, 10:12 pm | #4 |
Octode
Join Date: Jan 2009
Location: Falmouth, Cornwall, UK.
Posts: 1,990
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Re: Ekco CT102
Good write up, excellent result. The geranium transistor's made me laugh out loud.
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Stephen _________"It`s only an old telly" ___ |
2nd Jul 2014, 10:23 pm | #5 |
Octode
Join Date: Oct 2005
Location: Wimborne, Dorset, UK.
Posts: 1,407
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Re: Ekco CT102
A lot of work done already, well done!
Ive heard those sufflex caps can be trouble when they get this old. Very nice early chassis with the gy501 and pd500 in the smoke stack!! Cheers
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Lee |
2nd Jul 2014, 10:49 pm | #6 |
Pentode
Join Date: Mar 2009
Location: Norwich, Norfolk, UK.
Posts: 228
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Re: Ekco CT102
Thanks for the reply's guys. Sorry my spelling is not up to it. The small circuit board Frank is just multi way plugs for scan coils, tube base etc. Other work done was replace the 8.2meg resistors and change the grid leak 2.2meg to 820k on the CDA, realign the decoder, i had to replace the PD500 as the it was down to air.
The picture is very good, better then the 3 other single standard Pye's i have, and of course a lot more stable having the EHT shunt regulator |
2nd Jul 2014, 11:07 pm | #7 |
Dekatron
Join Date: Aug 2013
Location: Wigan, Greater Manchester, UK.
Posts: 9,433
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Re: Ekco CT102
Yes I can see the plugs etc in that photo. They had good pictures on them, I only saw a few and they did not give a lot of trouble.
The 390pf suflex was a common problem in the single standard sets, in fact the first thing I changed for no osc, the valve gave less trouble that the cap, replaced with a silver mica. I would put a couple of fuses in the LT PSU, with the bridge rectifier, if the diodes go s/c it can take out the TX, melted wax on the carpet and then the mains fuse blows. |
3rd Jul 2014, 3:42 pm | #8 |
Nonode
Join Date: May 2006
Location: St Albans, Herts, UK.
Posts: 2,193
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Re: Ekco CT102
3 other Pye Hybrids?!! That's more than me now! Nice result David.
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All the very best, Tas |
3rd Jul 2014, 4:00 pm | #9 |
Octode
Join Date: Aug 2006
Location: Willington, County Durham, UK.
Posts: 1,499
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Re: Ekco CT102
I have an Ekco CT102 stood at the back of a garage untouched for 34 years! I doubt it will be much use by now, Malc.
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Malc Scott |
4th Jul 2014, 1:37 pm | #10 |
Dekatron
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,921
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Re: Ekco CT102
Hi there
Looking at the pictures of the insides and all those wires it's no surprise many black and white engineers decided to call it a day when colour appeared! It's been said before but it's strange how, unlike most manufacturers, Pye started with a good design and over the years pared the costs down so much that the last hybrid, the CT205, was only a shadow of the original 'dual standard colur chassis' it was developed from, both in relaibility and performance. I can almost hear Tas on his way to relieve you of that CT102, Malc! Glyn |
4th Jul 2014, 5:43 pm | #11 |
Nonode
Join Date: Jan 2004
Location: 1966-1976 Coverack in Cornwall and Helston Cornwall. 1976-present Bristol/Bath area.
Posts: 2,965
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Re: Ekco CT102
Nice job and another fine example preserved for the future. I have also made the same mistake spelling ge transistors.
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Simon BVWS member |
5th Jul 2014, 10:22 pm | #12 |
Nonode
Join Date: May 2007
Location: Redruth, Cornwall, UK.
Posts: 2,573
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Re: Ekco CT102
That's a great result and the set is displaying quite a well defined picture. I am amazed that the LOPT is still serviceable after all this time. Did you give the LOPT a good dry out before testing the set? Those red solder mask PCBs were better than the later green versions.
Although I never actually worked on the dual standard version, I always liked the 691 single standard Pye hybrid. OK, they weren't to everyones tastes but they could display a very nice picture and were very easy to repair. I learnt a lot about colour television sets repairing the Pye hybrid 691 to 697 series which were bought for about £5 each back in 1981. The all transistor decoder is a good way to learn about PAL decoder processing and fault finding. It would be great to see some close up pictures of the chassis especially around the line output stage. Regards Symon. |
8th Jul 2014, 11:28 am | #13 |
Dekatron
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,921
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Re: Ekco CT102
Hi
One thing I never understood about the Pye hybrid was why the IF strip is amost like an afterthought, stuck up on the left. The most accessible panel was the most reliable - just the 4.7M resistor in the sync circuit needing changing once in a while. The B-Y - or was it the R-Y? - signal often used to fail, and it was surprising that the set managed to display quite a reasonable picture without it! Like Symon, I used to buy, repair and sell a lot of these and often you could buy a 205 with an earlier 691/3 thrown in free, and these latter ones always had the better panels so a good reliable modern looking set could be made up from the two, as long as you had a can of Evo-Stik and a staple gun to repair the 205's cabinet! Glyn |
8th Jul 2014, 6:37 pm | #14 |
Pentode
Join Date: Mar 2009
Location: Norwich, Norfolk, UK.
Posts: 228
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Re: Ekco CT102
Yes i agree, back in the day i used have these dual standards out on rent followed by the CT72 and 205 range. I always found the red decoder’s gave a better colour and of course the metal timebase in the CT72 was always a lot more reliable then the 205 printed circuit affair. I also had a lot of the Thorn 2000's out, my favourite by far, but no match picture quality wise. When the 2000's got a bit knackered i found it difficult to get customers to change to a more modern set, so used to fit a 3000 chassis into the cabinet. Had to remember to fit an isolated aerial socket though! Great times, i had a lot of fun. These sets had a lot of character.
I will take some more close up pictures when i have a chance. David |