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HH Scott LK72B Amplifier
#3

Before I opened the bottom of the amp, I had a bit of apprehension about my work as a teenager.  But, after close examination, I was fairly pleased with my layout and solder connections way back then!  I read a review of this amp a couple of hours ago and they reported as being very warm but not very bright.  It rolls off the highs a bit and works best with speakers that accentuate the the high end.  We'll see.  I tested all of the tubes and the 12AX7's, the 5AR4 and the 6U8's test ok, if not very good.  The output tubes, 7591s, are all very weak.  All tubes are original.  The 12AX7's are Telefunken and the 7591's are branded as Scott.  Not sure of the others as the identification markings are gone. Unfortunately, my sister lost the original assembly manual with the balancing instructions.  I found the schematic on line and hopefully will find the rest of the info I should have.  When I get to this project,  I'll re-stuff all of the capacitors, check all of the resistors, and replace the outputs with matched 7591's.  When this is finished, I'll tackle the tuner.


Messages In This Thread
HH Scott LK72B Amplifier - by rfeenstra - 03-25-2018, 06:00 PM
RE: HH Scott LK72B Amplifier - by Phlogiston - 03-25-2018, 08:59 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 03-25-2018, 10:51 PM
RE: HH Scott LK72B Amplifier - by morzh - 03-25-2018, 11:27 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 03-31-2018, 11:18 PM
RE: HH Scott LK72B Amplifier - by morzh - 04-01-2018, 09:59 AM
RE: HH Scott LK72B Amplifier - by rfeenstra - 04-01-2018, 05:25 PM
RE: HH Scott LK72B Amplifier - by morzh - 04-01-2018, 09:04 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 04-05-2018, 08:55 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 04-05-2018, 10:20 PM
RE: HH Scott LK72B Amplifier - by Phlogiston - 04-06-2018, 11:16 AM
RE: HH Scott LK72B Amplifier - by rfeenstra - 04-06-2018, 01:20 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 04-07-2018, 03:23 PM
RE: HH Scott LK72B Amplifier - by codefox1 - 04-30-2018, 09:44 PM
RE: HH Scott LK72B Amplifier - by Phlogiston - 04-30-2018, 10:22 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 05-01-2018, 12:18 AM
RE: HH Scott LK72B Amplifier - by morzh - 05-01-2018, 11:51 AM
RE: HH Scott LK72B Amplifier - by Phlogiston - 05-01-2018, 12:23 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 05-01-2018, 04:51 PM
RE: HH Scott LK72B Amplifier - by Phlogiston - 05-01-2018, 10:34 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 05-02-2018, 12:06 AM
RE: HH Scott LK72B Amplifier - by morzh - 05-02-2018, 08:23 AM
RE: HH Scott LK72B Amplifier - by rfeenstra - 05-02-2018, 08:55 AM
RE: HH Scott LK72B Amplifier - by Ron Ramirez - 05-02-2018, 09:45 AM
RE: HH Scott LK72B Amplifier - by morzh - 05-02-2018, 09:47 AM
RE: HH Scott LK72B Amplifier - by Phlogiston - 05-02-2018, 10:38 AM
RE: HH Scott LK72B Amplifier - by rfeenstra - 05-02-2018, 06:10 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 05-19-2018, 11:32 PM
RE: HH Scott LK72B Amplifier - by Phlogiston - 05-20-2018, 11:00 AM
RE: HH Scott LK72B Amplifier - by rfeenstra - 05-20-2018, 12:58 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 05-20-2018, 01:19 PM
RE: HH Scott LK72B Amplifier - by morzh - 05-20-2018, 02:18 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 05-20-2018, 02:34 PM
RE: HH Scott LK72B Amplifier - by KCMike - 05-20-2018, 03:01 PM
RE: HH Scott LK72B Amplifier - by Phlogiston - 05-20-2018, 03:27 PM
RE: HH Scott LK72B Amplifier - by TV MAN - 05-22-2018, 07:54 AM
RE: HH Scott LK72B Amplifier - by rfeenstra - 05-22-2018, 09:08 AM
RE: HH Scott LK72B Amplifier - by rfeenstra - 12-14-2019, 01:05 AM
RE: HH Scott LK72B Amplifier - by rfeenstra - 12-14-2019, 01:12 AM
RE: HH Scott LK72B Amplifier - by rfeenstra - 12-14-2019, 01:58 AM
RE: HH Scott LK72B Amplifier - by Phlogiston - 12-14-2019, 09:20 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 12-14-2019, 09:33 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 12-14-2019, 10:49 PM
RE: HH Scott LK72B Amplifier - by Phlogiston - 12-14-2019, 11:17 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 12-14-2019, 11:47 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 04-23-2020, 11:32 PM
RE: HH Scott LK72B Amplifier - by PhilcoJohn - 04-26-2020, 05:57 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 04-26-2020, 11:36 PM
RE: HH Scott LK72B Amplifier - by morzh - 04-26-2020, 11:48 PM
RE: HH Scott LK72B Amplifier - by rfeenstra - 04-27-2020, 01:37 AM
RE: HH Scott LK72B Amplifier - by MrFixr55 - 08-14-2022, 08:04 AM
RE: HH Scott LK72B Amplifier - by RGK20m3 - 08-15-2022, 07:17 AM
RE: HH Scott LK72B Amplifier - by rfeenstra - 08-15-2022, 10:13 AM



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