Today on the bench: my "Okano CM500" as sold by Karstadt. It's a Philips CM11342 chassis as was used in the CM8833-II monitor.
Really neat little monitor with a bright and clear CRT that I want to get many more hours out of.
A couple days ago the flyback frequency was a bit off on start up but stabilized soon enough. Then it popped, the vertical deflection collapsed and it let out the magic smoke.
Really neat little monitor with a bright and clear CRT that I want to get many more hours out of.
A couple days ago the flyback frequency was a bit off on start up but stabilized soon enough. Then it popped, the vertical deflection collapsed and it let out the magic smoke.
Fixed: TE-20 Signal Generator
This was a quick one. Only the lower bands were working and there was no modulation at all.
One band was taken out by a broken solder spot, the other upper two bands came back to life after reseating the 12BH7.
Modulation wasn't even working when being fed an external audio signal. Following the signal path revealed a short to ground. A capacitor leg was bend towards a solder spot and made contact. The internal audio oscillator only came back after fiddling with the capacitor on the right side of the Colpitts topology. Maybe it has an intermittent fault. Will get replaced, as will the filter electrolytics.
This was a quick one. Only the lower bands were working and there was no modulation at all.
One band was taken out by a broken solder spot, the other upper two bands came back to life after reseating the 12BH7.
Modulation wasn't even working when being fed an external audio signal. Following the signal path revealed a short to ground. A capacitor leg was bend towards a solder spot and made contact. The internal audio oscillator only came back after fiddling with the capacitor on the right side of the Colpitts topology. Maybe it has an intermittent fault. Will get replaced, as will the filter electrolytics.
Bun's Lab
It is here. HP1650B logic analyzer.
So sadly, I do not have the cables or probes/pods for it. And you cannot just buy those. Ebay sellers are asking absolute moon prices. The previous owner, Rik, tried to make his own using ribbon cables and little PCBs with termination resistors. But, he says, that didn't work so great. So this is something I gotta look into. Either source the original cables and pods, or make my own.