sluiting in afstemc. van B3X90U (Techniek Radio/TV)
door Mike Horne 
, 10.10.2016, 11:30 (2970 dagen geleden)
Hi. I am working on my Philips B3X90U radio, and have managed to power it up. The main let down is the tuning capacitor - the smaller front gang is alright, but the larger gang tends to short out about half way. This even happens on a replacement that someone kindly supplied me with. The odd thing is that the rotors do not seem to be touching the stator plates (I checked with a magnifying lens and lamp). The nut and bolt at the back is just for fixing the rotor and not adjusting the vanes. Anyone else experienced this problem, please?
Regards
Mike
sluiting in afstemc. van B3X90U
door Maurice 
, Dordrecht, 10.10.2016, 12:11 (2970 dagen geleden) @ Mike Horne
Mike.
Test the old one with just a Ohm meter
for short of that system.
Otherwise I think the oscilator shuts down at a high frequency because of other problems.
Or the 2nd is also defect.
sluiting in afstemc. van B3X90U
door Mike Horne , 12.10.2016, 12:55 (2968 dagen geleden) @ Maurice
Hi. I have disconnected all the wiring from the tuning capacitor but I still get short circuiting.
Anyone else got any ideas, or are there spare capacitors available?
Cheers
Mike
sluiting in afstemc. van B3X90U
door Mike Horne , 10.10.2016, 13:46 (2970 dagen geleden) @ Mike Horne
Hi Maurice.
Many thanks for your reply. I checked the rotor and stator vanes with an ohm meter and got continuity from about mid way to maximum capacitance on the large gang, the smaller front one seems to be working alright. I will check the oscillator circuit for other faults.
Mike