UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Hameg HM307-3 Cleaning and Repair

OldTechFan96 · 9th Jun 2019, 1:23 pm

I replaced the BF199 and nothing changed.

More voltage measurements (timebase off):

IC304:

Pin 1: +1V
Pin 4: -873V
Pin 5: -873V
Pin 6: 0V

T352:

E: -867V
C: -868V
B: -870V

T353:

E: -901V
C: -866V
B: -901V

I do have some CNY17-3 opto couplers. I may have a suitable diode to replace 1N4149, I'll have a look.

9th Jun 2019, 1:23 pm	#90
OldTechFan96 Octode Join Date: Jul 2017 Location: Newcastle Upon Tyne, Tyne & Wear, UK. Posts: 1,186	Re: Hameg HM307-3 Cleaning and Repair I replaced the BF199 and nothing changed. More voltage measurements (timebase off): IC304: Pin 1: +1V Pin 4: -873V Pin 5: -873V Pin 6: 0V T352: E: -867V C: -868V B: -870V T353: E: -901V C: -866V B: -901V I do have some CNY17-3 opto couplers. I may have a suitable diode to replace 1N4149, I'll have a look.