17-02-2019, 07:27 PM
That should work but it's a little bit low. Equivalent to using a rather old 1.5V battery. If the set is working then you can leave it. Otherwise the first thing to do is make sure you're on the correct mains tapping. Measure your mains voltage and set the tapping accordingly.
If that's OK, then check R15 and R16. Note that the resistance of the meter leads and the quality of the contacts they make will be significant when measuring low value resistors. You can check the meter leads by shorting them together and subtracting that reading from any measuement. It will often be around 0.4 ohms. Apart from that you're looking at replacing the 3 electrolytics C29,30,31. Modern 2200uF parts will be a lot smaller than the originals. Finally MR2 could be replaced by a couple of 1N400x diodes. Make sure you don't end up with too high a filament voltage after all this.
Reading the general notes see clip from trader sheet.
If that's OK, then check R15 and R16. Note that the resistance of the meter leads and the quality of the contacts they make will be significant when measuring low value resistors. You can check the meter leads by shorting them together and subtracting that reading from any measuement. It will often be around 0.4 ohms. Apart from that you're looking at replacing the 3 electrolytics C29,30,31. Modern 2200uF parts will be a lot smaller than the originals. Finally MR2 could be replaced by a couple of 1N400x diodes. Make sure you don't end up with too high a filament voltage after all this.
Reading the general notes see clip from trader sheet.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
