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512k vertical bars

Posted by: Cinan on 2020-11-01 16:12:45 I have acquired a 512k 120v model.  On first inspection the fuse was blown and diode at CR24 was burned out,  I have replaced these and done a complete recap of the electrolytic on the analog and logic board plus the RIFA CAP at C38.  On start up I get no bong and vertical bars as per the photo.  This is usually associated with a ROM issues,  I have pulled and reseated the ROMS and also re-soldered the ROM holders on the under side of the board with no change,  I will try with a logic board etc of a 128k but thought it worthwhile asking this group. One peculiar point is the top of C15-C17 on the analog board,  seem to have cuts in the top,  I haven't seen this before,  is this normal or do they need replacing ? View attachment IMG_7325.HEIC View attachment IMG_7324.HEIC View attachment IMG_7323.HEIC View attachment IMG_7317.HEIC

Posted by: Cinan on 2020-11-01 21:05:46 Some interesting updates.  I have tired the 512k Logicboard with he 128k Analog board (same result) and I have tried the 128k logic board with the 512k analog board and it works ok,  so the 512k analog bard is good. I have then swapped the ROM's from the 512k to the 128k and the 128k works ok,  so the 512k ROM chips are ok. I have tired the 128k ROM's in the 512k but it still does work,  so the 512k board is the issue not the ROM's or the Analog. I am assuming at the 128k ROM should work in the 512k board ?

Posted by: techknight on 2020-11-02 10:08:19 I cant open those files. not sure what a heic is.

Posted by: LaPorta on 2020-11-02 10:20:20 IPhone High Efficiency Image Codec (HEIC) files. Macs can open them no problem...I am assuming you are using a PC?

Posted by: techknight on 2020-11-02 10:24:28 Yeap, I dont own any modern apple products as I cannot stand modern apple. But thats my own prerogative.

Posted by: markgeek36 on 2020-11-02 10:26:17 have you checked the video board?

Posted by: markgeek36 on 2020-11-02 10:28:34 heic is not an apple format its an industry standard. however im not sure if Windows supports it. google supports it and there are converts you can download to convert it to jpg. i believe photoshop will read it as well.  heic is a mpeg standard however not everyone supports it yet.

Posted by: LaPorta on 2020-11-02 10:36:47 Yes you are correct however it was 99.9% likely those were iPhone generated, which is why I said as such.

Posted by: karrots on 2020-11-04 19:15:41 Windows can open it but you have to install the codec. https://www.microsoft.com/en-us/p/heif-image-extensions/9pmmsr1cgpwg?activetab=pivot😱verviewtab

Posted by: techknight on 2020-11-05 07:42:43 yea I dont use the UWP photo viewer, I absolutely hate it.  So I restored the windows-7 version of the viewer.

Posted by: Dog Cow on 2020-11-05 15:39:52 Here are his photos in JPEG format:

Posted by: techknight on 2020-11-09 06:17:36 CR23 through CR26 will need replaced for sure. if they dont show any faults now, they will soon.

Posted by: Cinan on 2020-11-09 13:14:37 Yes they have been replaced and the analog board is fine.

Posted by: bibilit on 2020-11-12 00:48:10 probably a Rom issue as you said in your post, you can have try swapping rom with another unit, probably with a Plus also.

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