Build Your Own Arcade Controls Forum
Main => Monitor/Video Forum => Topic started by: sevenleaf on October 17, 2009, 12:47:00 pm
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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?
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sounds like the crt is down to air-i.e neck is cracked
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Thanks Grant. I replaced the tube, but kept the same chassis, and got this: So your diagnosis in the tube was correct, thanks!
(http://img407.imageshack.us/img407/4960/dsc03058o.jpg)
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.
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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
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I bought the Sega Rally upright machine (listed as faulty (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=170369197326)) with a Hantarex 25" 25kHz chassis inside it. The fault was that the chassis kept blowing fuses (http://forum.arcadecontrols.com/index.php?topic=95875.0). After testing the rectifier diodes, unplugging and replacing the PTC, and everything else that was suggested (http://www.jammaplus.co.uk/forum/forum_posts.asp?TID=15806&PN=1) (didn't realise you were gunblade too :D) I bought a recently serviced and confirmed 100% working Hantarex 25" 25kHz chassis (complete with tube) (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290358544737&ssPageName=STRK:MEWNX:IT).
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?
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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
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I only have the new (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290358544737&ssPageName=STRK:MEWNX:IT) chassis with me at the moment, this is a photo:
(http://img8.imageshack.us/img8/2716/dsc03061tq.jpg)
(http://img12.imageshack.us/img12/975/dsc03062r.jpg)
I also have the green sticker from the fuse blowing original (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=170369197326):
(http://img9.imageshack.us/img9/7356/dsc03064e.jpg)
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?
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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