UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Microvitec Cub 1431 Power but no picture.

qsilver · 5th Apr 2018, 1:53 pm

Thanks for the replies, wanting to try and get back to this. What votlage am I looking for on D10? Just 115VDC? The reason I ask is my DMM goes up to 600V/1000V so I don't want to run the risk of damaging it if it could float quite high. Should I just clip a lead to the diode and measure?

Might sound obvious but I have not worked on one of these before and so I want to be as cautious as possible.

I have noticed some ROE capacitors in there that look reminiscent of those in a Cyrus amplifier which always went bad. I'm not sure which circuit they are on yet but I wonder...

As far as where this came from, I'm not sure where it originally was but it is possible it was from a school...

This CRT looks to be a Mitsubishi actually, reminded me of my Grandfathers old Mitsubishi TV with a flat screen over the CRT screen. I always remember it as having the best picture of all the TVs I was used to.

Nothing inside looks particularly hot or scorched so unless they did a great job in there with heatsinking, it probably hasn't led a very hard life but still could be joints I suppose.

There's now screeching or anything when it is powered on. You hear the degaus and thats it. No high pitched noises (I can usually here them) and no static feeling on the screen. Just the neon bulb.

5th Apr 2018, 1:53 pm	#10
qsilver Retired Dormant Member Join Date: Jul 2010 Location: Carlisle, Cumbria, UK. Posts: 66	Re: Microvitec Cub 1431 Power but no picture. Thanks for the replies, wanting to try and get back to this. What votlage am I looking for on D10? Just 115VDC? The reason I ask is my DMM goes up to 600V/1000V so I don't want to run the risk of damaging it if it could float quite high. Should I just clip a lead to the diode and measure? Might sound obvious but I have not worked on one of these before and so I want to be as cautious as possible. I have noticed some ROE capacitors in there that look reminiscent of those in a Cyrus amplifier which always went bad. I'm not sure which circuit they are on yet but I wonder... As far as where this came from, I'm not sure where it originally was but it is possible it was from a school... This CRT looks to be a Mitsubishi actually, reminded me of my Grandfathers old Mitsubishi TV with a flat screen over the CRT screen. I always remember it as having the best picture of all the TVs I was used to. Nothing inside looks particularly hot or scorched so unless they did a great job in there with heatsinking, it probably hasn't led a very hard life but still could be joints I suppose. There's now screeching or anything when it is powered on. You hear the degaus and thats it. No high pitched noises (I can usually here them) and no static feeling on the screen. Just the neon bulb.