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Marc
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PYE625 said
someone's nicked the 'flippin tuner cover. Why do I always seem to get an Ekco with a missing tuner cover? doh_gif

Ever thought of investing in a pair of tin snips and a few empty baked bean cans ? grin_gif

Marc.

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Posted : 03/03/2017 2:07 pm
PYE625
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Lol, it's tempting Marc at this rate.

Here are some pic's to browse, I'm going to have a lie down now after that long drive. zzzzzzz

rsz_img_2585.jpgrsz_img_2582.jpgrsz_img_2584.jpgrsz_img_2587.jpgrsz_img_2586.jpgrsz_img_2588.jpg

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Topic starter Posted : 03/03/2017 2:14 pm
Marc
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Well it doesn't look too bad Andrew, I see the usual crumbling on the LOPT surround (why do they nearly all do that ?) Should hopefully be a good 'un.

Marc.

PS. once you've got your tin snips working I'll place my order with you. wink 

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Posted : 03/03/2017 2:23 pm
Nuvistor
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At least the LOPTX windings are usually OK if they have not been too damp but the casing is as usual. Good clean of the dust and it will be like new. Look forward to following your progress, always liked this model series.

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Posted : 03/03/2017 3:18 pm
PYE625
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Hi, well I have removed the cabinet by following the instructions in the service data, plus the tube and then gave the chassis a brush and vacuum. It looks much better already, but as can be seen of the LOPT housing, something will need to be done about the decayed plastic. It looks to me like the high voltage has played a part in the decay as it is much worse towards the top where the overwind connection joins the top-cap cable of the EHT rectifier.

rsz_img_2603.jpgrsz_img_2611.jpgrsz_img_2610.jpgrsz_img_2614.jpgrsz_img_2617.jpg

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Topic starter Posted : 03/03/2017 4:18 pm
Nuvistor
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In the photo of the component side of the chassis, to the right of the scan coils and under the Egen variable control are two 2watt resistors, they change value and burn up, worth checking them, one from memory is 27k.

The LOPTX although requiring repair is not as bad as some I saw. The 2uf+500uf can on the Frame PCB fail.

I had forgotten the line output and boost diode valves were on a PCB, the PCB itself must have given little trouble.

After the clean up,it looks very tidy.

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Posted : 03/03/2017 5:06 pm
PYE625
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Thanks Frank, some good tips there.

Now, I remember Lloyd saying in his thread that he had no metrosil in his Ekco. Neither do I, well not one that is usable. It seems to have corroded away into powder. All I have left is the plastic tube waa_gif

I wonder if it is possible to make up a string of VDR's in series inside the plastic tube?  hmm_gif

 

rsz_img_2618.jpgrsz_img_2619.jpg

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Topic starter Posted : 03/03/2017 7:04 pm
freya
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I doubt you could make one, they do make a difference though when the picture changes from lots of dark to light. Without the picture balloons a fair amount.

The lopt overwind is encapsulated in some odd plastic coating that doesn't seem to get affected as bad as the wax or pitch types.

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Posted : 03/03/2017 8:10 pm
PYE625
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The LOPT overwind has a wax coating on mine.

Well I had a go at using a paxolin piece to replace the rotten LOPT connection support and am pleased with the result. It is nothing elaborate, but I was able to re-use the connection terminals as they are riveted and I was able to dill out the rivet and use some stiff wire to hold the two halves together through the paxolin strip. I used some nylon stand-off pillars and bolted it to the LOPT metalwork. 

rsz_img_2622.jpgrsz_img_2623.jpgrsz_img_2625.jpgrsz_img_2628.jpgrsz_img_2632.jpg

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Topic starter Posted : 03/03/2017 10:32 pm
Katie Bush
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It will be interesting to see how well that paxolin survives. I once tried using some to mount a high voltage cap in an HMV (oh, what was the model no?) Anyway, the paxolin started to self immolate as the set warmed up - full EHT - stinky fart kind of smell, avec urine du chat!

Not saying yours will fail the same way, but worth bearing in mind.

I have a 17" Dynatron with very similar EKCO chassis, and the same LOPT/EHT rectifier tray issue. I have been considering a clear polycarbonate/perspex type material to build a new tray.

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Posted : 03/03/2017 10:44 pm
Marc
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That paxolin repair looks good, one for the memory bank me thinks. hmm_gif

Marc.

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Posted : 03/03/2017 10:45 pm
PYE625
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Katie_Bush said
It will be interesting to see how well that paxolin survives.  

It will indeed. If not, it can easily be replaced with something more suitable.

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Topic starter Posted : 03/03/2017 10:52 pm
PYE625
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I have since discovered from the previous owner that it was retrieved from a disused flat above a bank that was closing down in Herefordshire and the set would have been thrown in a skip. Luckily, it was saved from such a fate.

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Topic starter Posted : 04/03/2017 12:26 am
Lloyd
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You were lucky to save that!

I like your replacement LOPTY casing, why didn't I think of something as simple as that? I made mine from paxolin too, so far it's not causing any trouble with EHT tracking.

Regards,

Lloyd

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Posted : 04/03/2017 1:18 am
PYE625
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Lloyd said
You were lucky to save that!

I like your replacement LOPTY casing, why didn't I think of something as simple as that? I made mine from paxolin too, so far it's not causing any trouble with EHT tracking.

Regards,

Lloyd  

Cheers Lloyd, but I have been admiring your re-creation of the LOPT casing because it is more faithful to the original design. Mine is rather a simplified version I'm afraid. (What I'm trying to say is I lack the skill to do it properly)   grin_gif

rsz_img_2629.jpg

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Topic starter Posted : 04/03/2017 10:21 am
PYE625
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This morning I have taken out the line PCB and replaced some components on it. Being removed from the set, it is easier to work on and clean up a bit too. Due to the problem of access when the tube is in place, I think it is far better to test and replace defective components now rather than struggle with it in place. Next, the frame stage PCB.

Here are a couple of snaps of the line PCB ready to go back in the chassis.

rsz_img_2634.jpgrsz_img_2635.jpgrsz_img_2633.jpg I think it pointless to expect these to be reliable. 

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Topic starter Posted : 04/03/2017 11:33 am
Nuvistor
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How far off 4.7k is that 3 watt carbon screen feed resistor? Agree a W/W component is much better and it needed to be replaced but those 3 watt resistors were pretty good.

The board is in excellent condition, just wonder how much use the set had.

The mod to the LOPTX, just a thought but the original shape shrouded the overwind, you may need to keep a check on any ozone with discharges to the screening can.

Looking forward to a nice bright picture on the TV.

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Posted : 04/03/2017 3:45 pm
PYE625
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Hi Frank, well the 4.7k is 4.6k so nothing wrong with it electrically. I will save it and likely re-paint it for another time.

The LOPT will be an interesting item to be keeping an eye on.  wink

Well I have had the frame board out and replaced all the faulty components, the usual capacitors, but the resistors all check ok. The dual can electolytic reformed nicely, an unusual type containing a 2uf 150v and a 500uf 25v section.

Both boards are back in situ now and I will begin to check components on the main chassis. I have checked the main smoothing can and it is fine, it has been replaced at some time in the distant past with an RS type. No doubt the wax capacitors and the Hunts mouldseal types will reveal no great surprises as to their condition. Unlike the Ekco TMB, there are none of those numerous horrible capacitors with coloured bands to replace.

rsz_img_2639.jpgrsz_img_2640.jpgrsz_img_2636.jpgrsz_img_2641.jpg

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Topic starter Posted : 04/03/2017 3:57 pm
Nuvistor
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Did you check MR1 the interlace diode while the PCB was out? 

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Posted : 04/03/2017 4:22 pm
Marc
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Hi Andrew,

Just thought I'd show the photo below as an alternative simple Ekco LOPT cover I spotted some time back....

Marc.

Ekco-LOPT-Cover-1.jpg

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Posted : 04/03/2017 4:34 pm
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