Clean H. H. SCOTT LK-72 TUBE AMPLIFIER NO TUBES AS-IS for Parts/REPAIRS/Restore

  

NOT WORKING, For Parts or For repair Restoration. Has been stored in a Box in an Climate Controlled Closet for 40+years.

It has not been powered up in years. Only Initial testing for good transformers, which are good.

(READ FULL TEST DESCRIPTION BELOW). Excellent Cosmetic physical condition and very clean. This unit would be a very good candidate for a full restoration. NOTE: The last 4 of 24 pics show this unit under test with a set of new test vacuum tubes, however this sales DOES NOT INCLUDE TUBES. I removed the bottom cover to show you the inside of the chassis.

This unit appears to be all original with caps and resistors that are 63 years old. I bought this unit because I needed the tubes for my fully restored Fisher 500C (family airloom). I started a minor restoration on this unit just cleaning it up. We Deoxited all the front-end controls which are all functional (working as designed) installed a new 2 1/2 Amp fuse and cleaned all the tube sockets with CRC-QD electrical contact cleaner, Removed the bottom panel checked all the solder connections which were all good (no burn marks or open solder points) and sprayed all the solder joints with CRC-QD. We then installed a complete set of newer tubes to test the unit out and brought the unit up slowly on a variac to warm up slowly the internals.

The GZ34 Rectifier and the 4x 7591 output tubes and the 2x 7199 (6GH8) tubes all lite up very nicely however the four new 12ax7s did not lite up. We had 2 input devices connected CD into the'Spare' input and a Cassette Tape plugged into the'Tape' input and connected 2 speakers. As we toggled the front controls to workin the Deoxit we heard different levels of static coming from the speakers but no audible music from the input devices. So for a restoration I would start by replacing all the front end caps (six white wax caps 0.1mf/0.022mf at 400VDC with 6x 0.1mf /0.022mf at 600VDC and replace the two brown 4MFD caps and the two white 0.1 400VDC cap toward the back of the unit, all scene in pics) and check all the front-end resistors. This unit has several multi-stage electrolytic'cans' which need also testing.

Specs and Details of the H. Scott LK-72 Integrated Amplifier change'dot' to a period'. Hifiengine dot com/manual_library/hh-scott/lk-72 dot shtml.

More Notes: A nice high-quality PDF scan of the HH Scott LK-72 Schematic is available to download for free at Hifiengine dot com free to register, a good website for product info, reviews by audio owners and for free documentation and restoration hints, tips ect.