Hantarex Polo question

[sevenleaf]

I have just bought another Polo (confirmed working, direct replacement) as I am having no luck fixing my other one.

I plugged it in, switched it on, had a bit of fizzing, and now the neck just fires up purple and then off, flashing. Screen shows nothing.

Any idea what's up?

[grantspain]

sounds like the crt is down to air-i.e neck is cracked

[sevenleaf]

Thanks Grant. I replaced the tube, but kept the same chassis, and got this: So your diagnosis in the tube was correct, thanks!



From research I think it's vertical frame collapse but I have only seen cases of this with a thin white line before, not like this.

I don't have a test rig yet so can't test voltages. I have a spare TDA2593, have ordered a TDA1675 and an R167 (flame proof) so will just try replacing parts. Anything else I should change whilst I'm placing an order? Have found a cheap parts supplier.

[grantspain]

can you go over exactly what you have done/swapped
i have a sneaky feeling that you may have a mismatch on the chassis/yoke even though it looks like a vertical collapse/foldover

[sevenleaf]

I bought the Sega Rally upright machine (listed as faulty) with a Hantarex 25" 25kHz chassis inside it. The fault was that the chassis kept blowing fuses. After testing the rectifier diodes, unplugging and replacing the PTC, and everything else that was suggested (didn't realise you were gunblade too ) I bought a recently serviced and confirmed 100% working Hantarex 25" 25kHz chassis (complete with tube).

I plugged the new chassis into the old tube and got the fizzing and then the purple flashes.

After your air suggestion I removed the original tube and put the new chassis back in with the new tube and got the above picture, and the smell of smoke, at which point I quickly took the picture and switched it off. A mate that was with me said the colour was changing slowly.

Do you think the initial fizzing blew something and caused this?

[grantspain]

well personally i think you have a polo 2 on a polo 1 crt hence the vertical deflection problem
i would need you to post photos of both chassis and read the yoke resistance witha multimeter to be sure

[sevenleaf]

I only have the new chassis with me at the moment, this is a photo:





I also have the green sticker from the fuse blowing original:



I've looked up pics of the Polo/2 and really don't think either chassis are a 2. Both have come from site as a tube/chassis combo so don't think a mismatch would have occurred? Will measure yoke resistance at the weekend and post back.

Is it worth me swapping ICs now and trying that this weekend too?

[grantspain]

the chassis numbers match but i do not remember a fixed 24khz polo 1 chassis,i remember a dual sync manual switch polo 1 chassis
i would wait for the yoke value before swapping ic,the ic is the tda 1675 for vert deflection