UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Help needed with

3pinplug · 13th Feb 2023, 8:45 pm

Hi all
Firstly apologies for my last post, i thought i had typed more but it didn't appear.

Hopefully this one is back to normal!

All set at 5V Ampl / Div

TP15 - No trace observed or movement on oscillocope, measures 0.00v on DVM when checked.

Pin 2 of IC22 - yes i get the series of negative pulses

Pin 2 IC21 & Pin 10 IC22 - see the same waveform present on both pins.

TP8 - No trace observed or movement on oscilloscope, measure 0.00v on DMM.

Pin 9 IC21 at 12v, Pin 8 at 0.00v

IC26 Pin 13 no trace observed or movement, 0.00v on DMM.

The trace you suggested may be noise i would agree with, as I really had to hunt to display that.
Thanks again to you all for your continued help
Mark

13th Feb 2023, 8:45 pm	#93
3pinplug Pentode Join Date: Jun 2016 Location: Kent, UK. Posts: 190	Re: Help needed with - Racal Dana 9081 Hi all Firstly apologies for my last post, i thought i had typed more but it didn't appear. Hopefully this one is back to normal! All set at 5V Ampl / Div TP15 - No trace observed or movement on oscillocope, measures 0.00v on DVM when checked. Pin 2 of IC22 - yes i get the series of negative pulses Pin 2 IC21 & Pin 10 IC22 - see the same waveform present on both pins. TP8 - No trace observed or movement on oscilloscope, measure 0.00v on DMM. Pin 9 IC21 at 12v, Pin 8 at 0.00v IC26 Pin 13 no trace observed or movement, 0.00v on DMM. The trace you suggested may be noise i would agree with, as I really had to hunt to display that. Thanks again to you all for your continued help Mark