Help restore an RCP 413 tube tester
Hi all, I'm not sure this is the right forum...., but I couldn't find any better! Is anyone here familiar with this Radio City Products tube tester? It must be over 60 years old and I'm restoring it. A circuit diagram is attached below.
While giving it a thorough clean-up and varnishing the wooden case, I changed the capacitor (C1) to .047uF/400V and fitted the neon lamp which was missing. A new mains cable was also fitted. I checked the other components (resistors, rheostat, pots.) and the meter and they all measure OK.
The first three functions of the tube tester (i.e. (a) Short and Leakage test, (b) Filament Continuity and (c) Cathode Leakage) are performing properly. When I do the Quality Test (following the instructions on the owner's manual) the meter pointer remains static at 0 (lowest level of 'poor' quality!!).
I tried several valves (all octals, known to be working - there is no provision for 9-pin valves (!), but I intend to insert one), and not one of them managed to move the meter pointer...!! I checked the valve-holder for possible wire breaks; - nothing.
Can anyone help with ideas or suggestions.
Thanks in advance.
The phone jack socket was not making contact -- open circuit.
For members with similar problems with test gear I can recommend this site:
Regards to all.
|All times are GMT. The time now is 06:52 AM.|
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2015 DragonByte Technologies Ltd.
Copyright ©1999-2015 diyAudio