Assessing The Ultra 3500 from Lucien's collection.

[Welsh Anorak]

Looks far better than the rentals that were sent out back in the day!

Looking forward to seeing a picture on it - they always gave good results - far better than the budget 8500/8800 IMHO.

[slidertogrid]

Many thanks! Yes I am pleased with how it has turned out. The Fablon and edge
trim is a good match. Thanks for the recommendation 19Seventy7 !

It's back in its box. I have put the original frame and line panels back in. So far only the line panel and frame panel have needed repairing. The decoder. RGB I.F and more surprisingly the power panel are as they came.

The picture is pretty much as it came on. There is some setting up to do. It also loses the signal intermittently probably just the multi turn pots playing up.
I need to investigate intermittent brightness level. the brightness will fluctuate occasionally - the controls still work though at either level.
I noticed this fault before I took the set apart but I didn't see it when the frame and line panels were being repaired in the other set which suggests the fault is on another panel...
ISTR that the pot on the top of the frame board should be adjusted for 0V on the grids. This will not set up, the voltage is constantly fluctuating.

The focus also drifts slightly and the control is near one end. The Tripler is a replacement so maybe nothing more than a resistor drifting? The set probably hasn't been powered up for 30 years or more? So it can be forgiven for a few little problems arising as it wakes up...

[slidertogrid]

Originally Posted by TonyDuell

Don't forget the 'Canvas apron to protect those other precious parts' as the Whitechapel MG1 technical manual puts it.

Ha ha I had to think about that for a moment... Yes all delicate parts were adequately protected! I expect a 22" 90 degree tube would go with a fair old bang!
Today I have run the set for a little longer to see if it settles down or if it will need further attention. It does seem to be getting better. Tomorrow I'll set it up by the manual. I have cleaned the tuner pots and the tuning has so far remained stable.... Fingers crossed!


A picture of the parts replaced so far from the line and frame panels. Not that many really.

[agardiner]

Wow. What a transformation from when you started.

[1100 man]

What a splendid end result - well done!!

Fablon is wonderful stuff and I, like many others here, used it to good effect to recover cabinets in days of yore (whenever they were!)

There was a trend for 'black ash' cabinets for second hand sets during the '90's - wood colour was so old fashioned! Fablon did a great job, although some cabinet designs didn't lend themselves to being covered in this way.

Excellent choice of vintage material too - I used to get home from school and watch Scooby Doo on our brand new G11 in the early '80's!

I'm sure Lucien would be well impressed to see what you have achieved with this rather battered set!

Cheers
Nick

[19Seventy7]

Wow, what a result! If I didn’t know any better I’d have thought it was a totally different set!

The tube looks a cracker, as does the picture it displays. Well worth the efforts to get it going! As Nick says, you’ve done Lucien and this set proud.

Glad the recommendation worked out! As I say it’s matched a few of my Thorn sets rather well, and the iron on front looks great too.

Seeing this has made me want to get my 3000 up and running - that’ll be next after I complete the 1400!

‘77

[slidertogrid]

Thanks for all of the kind comments. I am pleased with how it has turned out. Running it yesterday it has improved the focus drift and intermittent brightness variation has settled down. Replacing the set Grid volts pot has sorted the brightness the focus has settled down on its own maybe as the spark gap and thick film focus unit has dried out.

Then the line appeared....

I pinned the fault down to the line panel. The line was affected by the setting of the brightness control and also reduced the gain as when the signal was removed the raster went blank rather than snowy.
I rechecked the capacitors that had been tested rather than replaced. I checked for dry joints and any arcing or 'fizzing'. Then to be honest I got lucky. I spotted a little hidden brown Hunts on top of the line panel under the heatsink so it wasn't visible when the beam limiter panel was removed. I missed that one when I checked the others! It was cracked and would have been changed on sight if I had seen it previously.
It was soon replaced. C531 wired between the collector and emitter (earth) of the line driver Transistor so a prime suspect for the symptoms I had.

It's not a part I remember changing back in the day maybe it was a common fault that passed me by? My other line panel has a yellow capacitor in that location that looks original. This set is a late model so it looks as if the quality dropped as time went by...

[Stuart R]

Brilliant to see this one alive and kicking again - like the Mouse Pye, it looked beyond hope!

I'm glad to see the sets have found an enthusiastic owner - that's definitely so, going by the other radios and TVs spotted in the background

SR

[slidertogrid]

Thanks Stuart. Yes it is in good company! It has started to throw up a few faults. The gain would drop randomly and quickly come back until yesterday when the picture went snowy and stayed that way. The Varicap tuner had given up. Luckily I had a spare and that has sorted that fault.

Running the set today the colour went off! Not surprising really as the decoder hasn't had any attention, two small black .47 uf Callins type capacitors were splitting and one had lost half of it's encapsulation. Replacing them made absolutely no difference of course. Tomorrow I'll override the colour killer and see what happens...
Never a dull moment!

[Andrew2]

So nice to see a 3500 working so well after all this time. We had loads of 3's and 35's out on rent along with many 8's and 85's and apart from a few stock faults they were pretty decent sets.
The only regular faults I recall were the 30v smoother that went low and cause a 'no start' condition and the black electrolytics on the AGC line which could cause fluctuating contrast and flashing. Never had a LOPTX failure although a few R2010's packed up, as did the LOP transistor R2008 (?). Oh and the 1.5 ohm ww in the beam limiter. Good tellies.

[slidertogrid]

Yes I was the same when I first started self employed I bought 3500s and 8500s for cheap rentals. I got some really nice sets from a local firm that bought another firm's rental accounts. They changed them all over as they didn't carry spares for Thorn sets. Some engineers didn't like them either...

Overriding the colour killer made absolutely no difference. Luckily this time I wasn't faced with multiple faults like the previous 3500 decoder in which I had duff Transistors, capacitors and the Crystal faulty.

I put the board in the other set on the bench, insulated the bottom of the panel from shorts with a bit of cardboard and hung the decoder out of the back of the chassis and made a few voltage checks. I found no Emitter Volts on VT304 and it's a Lockfit! Always a good bet for a duff Transistor. I replaced it and away we go. Blimey! I had set aside three days! Returning the panel to the set and we still have colour. So on soak test again. I told it - Any more of this and you go on the "untested" ex-rental pile!!