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Philco model 18 (code 121) - HELP!
#67

Your 32K resistor probably melted due to incorrect wiring of the cap 2uFto Chassis.

I do not have 121 sch but on 124 those parts are Resistor #55 and cap #40 (part C of the multiple electrolytic). You probably shorted the resistor to GND when your cap went bust when probably wired backwards.

PS. That resistor has DC path to the chassis so it cannot be accurately measured in-circuit. The top part has a path to GND through the output transformer and Resistor 6.5 kOhm, and the bottom part has another resistor to GND. I cannot read the bottom resistor value.

So your resistance is (32K + Rtrans-prim + 6.5K) * Bottom Resistor / (32K + Rtrans-prim + 6.5K + Bottom Resistor).

If the bottom resistor is 50K then it will probably be on the order of 22K total.


Messages In This Thread
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-07-2013, 10:22 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-08-2013, 10:32 PM
RE: Philco model 18 (code 121) - HELP! - by Arran - 02-08-2013, 10:49 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-09-2013, 02:21 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-09-2013, 05:57 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-09-2013, 06:12 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-13-2013, 08:40 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-21-2013, 05:25 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-28-2013, 06:04 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 03-07-2013, 04:16 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 03-07-2013, 11:20 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 04-17-2013, 01:25 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 04-18-2013, 08:48 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 04-18-2013, 09:49 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 04-29-2013, 10:02 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 06-12-2013, 01:37 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 06-13-2013, 08:33 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 07-23-2013, 10:33 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 07-24-2013, 11:11 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 08-02-2013, 05:06 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 08-21-2013, 10:26 AM
RE: Philco model 18 (code 121) - HELP! - by morzh - 12-17-2013, 10:58 AM
RE: Philco model 18 (code 121) - HELP! - by morzh - 12-19-2013, 12:47 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 12-19-2013, 08:48 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 01-17-2014, 04:05 PM



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