4th Jul 2011, 10:37 pm | #61 |
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Re: HMV 900 TV restoration.
That's exactly what I have done on several radios and TVs. It's quite easy to make the boxes out of sheet brass, solder them together and spray them silver or green etc. leaving the base open as I suggested in my previous post. It looks so much better, especially when the blocks are mounted on the top of the chassis. In the 900 however, it seems that they are under the chassis so are not seen but nor are the wax caps that you are going to stuff! I would definitely go for it - you and Mike will know they are there.
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5th Jul 2011, 3:23 pm | #62 |
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Re: HMV 900 TV restoration.
I have now removed the offending faulty EHT transformer and checked the HT/Heater transformer as OK (tested for leakage and applied Mains)
I have roughly cleaned up the chassis with a wire brush and these little cooper brushes in the drill. The chassis looks so much better and it will certainly come up well with the proper treatment.
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5th Jul 2011, 5:25 pm | #63 |
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Re: HMV 900 TV restoration.
Hi Everyone,
For the next stage of the cabinet restoration my attention will be drawn to the veneer work on the front. Those who saw the set at the Warwick Exhibition Centre will remember it was not in good shape. The pictures show the cabinet rear batten and those blocks used to attach the batten to the rear edge of the floor. I call those blocks "assembly blocks". Is that correct term? The other picture shows that the original side panel has parted slightly from the new rear batten. I've redone that joint and fitted an inside corner block. DFWB. |
5th Jul 2011, 5:48 pm | #64 |
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Re: HMV 900 TV restoration.
Hi David
I think those blocks are just called "glue blocks". That's how I have heard them referred to. |
5th Jul 2011, 6:16 pm | #65 |
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Re: HMV 900 TV restoration.
Hi Brian,
"Glue blocks" I believe that is the correct term. DFWB. |
5th Jul 2011, 10:01 pm | #66 |
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Re: HMV 900 TV restoration.
Ed Dinning made me what was an essentially new EHT TX for my 702. Mike Barker does excellent rewinds of these TXs. Suggest you ask both of them for quotes.
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5th Jul 2011, 10:05 pm | #67 |
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Re: HMV 900 TV restoration.
Thanks Jeffrey. I certainly will do.
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5th Jul 2011, 10:22 pm | #68 |
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Re: HMV 900 TV restoration.
I have also used both Mike and Ed for EHT transformer rewinds and I can recommend them both.
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12th Jul 2011, 1:24 pm | #69 |
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Re: HMV 900 TV restoration.
Hi.
While I am awaiting the EHT transformer rewind I have now put the sync and RF unit onto the bench. There is a lot of evidence of previous work there are a few caps missing and a number of disconnected cables. It certainly is not the worst I have tackled and barring snags should be a working chassis soon.
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12th Jul 2011, 1:30 pm | #70 |
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Re: HMV 900 TV restoration.
Glue blocks ,I seem to call them Rub blocks, probably because they are applied by having glue applied to two surfaces then rubbed in place till they stick
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13th Jul 2011, 5:32 pm | #71 |
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Re: HMV 900 TV restoration.
From what I can see some of the 240 line circuitry is still in place. There are wires cut all over the place and lots of caps have been replaced with non standard types possibly in the late 40's and 50's.
What I really could do with is an original manual with the 240 & 405 line circuitry and some hi resolution pictures of a restored set, this would help me out with snipped out wires and components. I have checked out all the tuned circuits and they "look" in nice condition, not even a spiders skeleton inside! There is a lot to be done though as there are so many wrong caps and a goodly few paralleled up resistors.
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13th Jul 2011, 10:30 pm | #72 |
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Re: HMV 900 TV restoration.
Hi Trevor
I can't give you pictures from an actual set but here is the circuit of the dual standard 900 timebase chassis. It's from the Omnibus service manual for EMI pre-war TVs. I'll email it to you if you PM me with your email address. |
19th Jul 2011, 12:52 pm | #73 |
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Re: HMV 900 TV restoration.
The front bottom right hand corner was damaged by woodworm and required reconstruction.
The first picture shows the damage and the second pic shows the repaired area. DFWB. |
19th Jul 2011, 1:33 pm | #74 |
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Re: HMV 900 TV restoration.
That's a very tidy repair, David. Well done.
How did you secure the repair section in place? Is it simply glued, or did you use some additional techniques to provide greater strength? I have to smile, because a few folk at the NVCF were convinced that an entire new cabinet would need to be made. Personally, I doubted that very much, and am delighted to see the repairs coming along so well.
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19th Jul 2011, 3:49 pm | #75 |
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Re: HMV 900 TV restoration.
Hi Ian,
The cabinet is constructed from veneered blockboard which is 21mm thick. That figure is used in all the parts of the cabinet. The repair was easy. All that was required was a piece of wood which was 2mm thinner than the original, glue it into place and finally trim back the surrounding outer 1mm veneer and then glue in a new piece to make a smooth surface. The veneer piece overlaps the joints and adds some extra strength to the repair. A 45 degree mitre cut was made to allow the new part to come into contact with side part. The surface will be veneered later along with rest of the cabinet that needs refinishing. Actually, three quarters out venner is still in good condition DFWB. |
19th Jul 2011, 4:02 pm | #76 |
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Re: HMV 900 TV restoration.
This is a fascinating thread David. I was able to get to the Warwickshire event for the first time this year so, having seen this set in it's original sorry state, it's great to find out what happened subsequently.
Best Wishes, Dave W |
20th Jul 2011, 8:12 pm | #77 |
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Re: HMV 900 TV restoration.
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20th Jul 2011, 10:24 pm | #78 |
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Re: HMV 900 TV restoration.
From what I know of David's work, we ain't seen nothing yet!!
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1st Aug 2011, 4:10 pm | #79 |
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Re: HMV 900 TV restoration.
Time is running out. If possible, I must try to complete this job within two weeks.
I've reveneered the front right corner of the cabinet. DFWB. |
1st Aug 2011, 8:26 pm | #80 |
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Re: HMV 900 TV restoration.
That looks superb!
Peter |