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Old 14th October 2002, 02:10 PM   #11
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Location: Richmond, VA
John,
Considering your overheating issue mentioned in your initial post, I see you have noticed the amp runs hot due to a lack of ventilation. If I might make a suggestion, please check that the spacing between the output transformers and the chassis is adequate. The transformers are on spacers, and a lot of hot air can escape form the large holes under the trannies.
Good Luck,
Joe E.
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Old 14th October 2002, 09:11 PM   #12
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Location: Fairbanks, Alaska
Default Progress and transformer spacers

I have had a chance to strip the amplifier down to its bare chassis, remove all parts form the terminal boards and clean them.

There were spacers under the power and output transformers. There was some wax potting compound that had leaked from the power transformer down its wires that I need to heat up and clean off. I also found out that the transformers had been repainted without having been removed from the chassis. The transformers have sort of a semi glossy finish while the color of the chassis appears to be flat brown.

Besides repainting the transformers again, I would like to repaint the chassis and hide the scratches at various places and also the engraving that was done on the rear side. Perhaps some bondo will be required to fill the engraving that appears to have been done by the original owner.

Repainting the chassis would of course eliminate all gold colored markings on the chassis. I took some pictures of these so I would be able to restore them the best I can if I decided this to be worthwhile. Restoring the marking on the chassis would be a time consuming job and it would never look exactly like the original. At the present time I want the amplifier it to look very good when Iím done and the markings on the chassis are actually not very important to me.

I also discovered that the output terminal strips had been replaced at one time as evidenced by 4 new holes that were not precisely drilled to mount the new strips. The is also a 7/8 inch hole that had a plate with a ľ inch phone jack mounted in it on the left side of the chassis that I will need to cover up. All other work that had been done to the amplifier appears to have been various repairs to the circuitry itself. Those repairs were of poor workman ship, but workable.

Now I will need to find some suitable paint and wire before I can continue.

John Fassotte
Alaskan Audio
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Old 14th October 2002, 11:40 PM   #13
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John,
A mod I made that I did not mention was to replace the speaker terminal strips with binding posts. I used 4 pairs (2 pair per side) for access to all impedences. You could use only 1 pair per side if you know which impedence you will use. This may be an unacceptable alteration to some, but I considered this as an acceptable upgrade. The only real damage is to enlarge holes to the appropriate size.
Joe E.
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Old 15th October 2002, 12:05 AM   #14
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Joe,

I think I will also convert to the binding posts for the output connectors. Four per channel sounds good to me. This would allow access to each output impedance with no problem.

The binding posts will sure beat the small screws of the original terminal strips. I may have some laying around that I can use.

John
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Old 15th October 2002, 01:03 PM   #15
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John,
Another thing I did was to add a power switch on the Primary side of the PT. A switch was not stock. I really didn't like the amp's reaction to plugging and un-plugging the power cord. I removed the convenience outlet to mount my toggle switch. I was thinking you might put a switch in the big hole on the side since its already there.
Joe
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Old 15th October 2002, 03:21 PM   #16
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Default Power switch and power cord

Joe,

The hole on the side is to close to one of the driver tubes and thus it would not be a good idea to run 117vac near that location. However I do like your idea and use the old ac outlet possition to add a power switch.

The AC power cord will also be replaced with a three wire one for safety. Jim included a new power cord in the package he sent me to do this. The new power cord can use the stock strain relief.

John
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