Search found 40 matches

by gkmaia
Sun Jan 05, 2020 5:26 am
Forum: Samplers
Topic: What software is used to write the EPS249OS.hfe image to a floppy?
Replies: 13
Views: 4790

Re: What software is used to write the EPS249OS.hfe image to a floppy?

Thanks for the help. I did manage to get omni flop, install & license it. Test installation returns the drive supports the Ensoniq 800k formats plus auto sense. Test BIOS drive type returns 3.5" 1.44MB Formatted MF2-DD disks in a few different formats but when using the diagnostic diagnostic tool it...
by gkmaia
Sat Jan 04, 2020 10:14 pm
Forum: Samplers
Topic: What software is used to write the EPS249OS.hfe image to a floppy?
Replies: 13
Views: 4790

What software is used to write the EPS249OS.hfe image to a floppy?

I got a desktop with windows XP and an internal floppy drive. I could try to write the EPS system floppy myself as I have the OS image file already.

Would you be able to let me know what windows software is used to write the EPS249OS.hfe image to the floppy?
by gkmaia
Sat Jan 04, 2020 10:12 pm
Forum: General Synthesizers
Topic: Ensoniq EPS - disk not formated issue
Replies: 5
Views: 1914

Re: Ensoniq EPS - disk not formated issue

I did a few more tests and hooked my logic analyser to the buffer that drives the data flow from the drive to the FDC and communication is happening as expected. If there is no disk in the drive the EPS prints "no disk". If there is a FAT16 disk the EPS disk prints "disk not EPS type". This means th...
by gkmaia
Fri Jan 03, 2020 7:47 am
Forum: General Synthesizers
Topic: Ensoniq EPS - disk not formated issue
Replies: 5
Views: 1914

Ensoniq EPS - disk not formated issue

I am trying to bring an old Ensoniq EPS to life. Initially it was not even starting up. Then found it had 4 of DRAM ICs faulty. Replaced them now it loads the initial software present on the EPROMS and ask for a system disk. Then I got a newly recorded EPS v2.49 floppy from Ebay. Tried it, drive spu...
by gkmaia
Sun Nov 17, 2019 3:47 am
Forum: HELP!
Topic: Korg 35 filter testing circuit
Replies: 0
Views: 966

Korg 35 filter testing circuit

I am trying to build a testing circuit for a Korg35 as per bellow. Has anyone here attempted to build this this circuit? If so... what would be VI (has not description on the schematics, is it input or output?) and what would be the expected Vout peak-peak voltage? Thanks in advance. http://www.anal...
by gkmaia
Sun Oct 13, 2019 6:03 am
Forum: HELP!
Topic: Ensoniq EPS issue
Replies: 3
Views: 2254

Ensoniq EPS issue

I bought a second hand EPS (not the 16, the standard one). Got the ALL leds no display issue. Power supply is fine. The keyboard to main pub cable has been re-crimped. MC68000 MPU seems to be managing the control, address and data bus. MC68440 DMAC seems to be also doing its job pulsing addresses to...
by gkmaia
Sat Aug 31, 2019 8:48 am
Forum: HELP!
Topic: M-Audio Prokeys 88SX board needed
Replies: 0
Views: 1296

M-Audio Prokeys 88SX board needed

I got an M-Audio Prokeys 88SX which has a faulty SAM9708 IC and I am just trying to find if anyone here has one of these that is maybe not working and would be interested in selling the main PCB.
by gkmaia
Wed Jan 23, 2019 9:32 am
Forum: HELP!
Topic: D-50 sounding distorted, noise & creaking
Replies: 22
Views: 6522

Re: D-50 sounding distorted, noise & creaking

I did manage to create a clean patch by "init" the partials. It sounds clean and perfect.

But as soon as I start messing with chorus look what happens... seems chorus flanger options 3 and 4 are completely busted.

by gkmaia
Thu Dec 27, 2018 9:52 pm
Forum: HELP!
Topic: D-50 sounding distorted, noise & creaking
Replies: 22
Views: 6522

Re: D-50 sounding distorted, noise & creaking

Try contacting the seller in the ebay link. Read the description. Maybe the item didn´t sell or the seller still has one available. Good luck. http://forum.vintagesynth.com/viewtopic.php?f=5&t=102457&hilit=crackling&start=45#p806128 I am wondering what would happen if I just remove the Chorus chip ...
by gkmaia
Thu Dec 27, 2018 9:14 pm
Forum: HELP!
Topic: D-50 sounding distorted, noise & creaking
Replies: 22
Views: 6522

Re: D-50 sounding distorted, noise & creaking

Try contacting the seller in the ebay link. Read the description. Maybe the item didn´t sell or the seller still has one available. Good luck. http://forum.vintagesynth.com/viewtopic.php?f=5&t=102457&hilit=crackling&start=45#p806128 Thanks Mooger5. I will do that. I ordered all new RAM ICs as I hav...
by gkmaia
Thu Dec 27, 2018 2:42 am
Forum: HELP!
Topic: D-50 sounding distorted, noise & creaking
Replies: 22
Views: 6522

Re: D-50 sounding distorted, noise & creaking

No luck. Unfortunately. These are the last updates: - New PCM54 DAC installed - Chorus IC & Chorus RAM IC removed, checked and cleaned at 20X magnification. - Checked all traces from-to Chorus and Chorus RAM ICs. And they are all fine. No shorts or fails. - Chorus IC & Chorus RAM IC welded back and ...
by gkmaia
Sat Dec 22, 2018 8:45 pm
Forum: HELP!
Topic: D-50 sounding distorted, noise & creaking
Replies: 22
Views: 6522

Re: D-50 sounding distorted, noise & creaking

Looking at the chorus IC pin table would you know what results to expect on a logic probe?

Image
by gkmaia
Sat Dec 22, 2018 7:57 pm
Forum: HELP!
Topic: D-50 sounding distorted, noise & creaking
Replies: 22
Views: 6522

Re: D-50 sounding distorted, noise & creaking

What about the chorus chip? I am not sure yet. Waiting my sram socket to arrive so I can attach it with a socket instead of soldering directly to the PCB. After that I will turn it on again and test it. But till then just waiting. It would be good to know more how to test the chorus IC with a probe...
by gkmaia
Sat Dec 22, 2018 6:25 am
Forum: HELP!
Topic: D-50 sounding distorted, noise & creaking
Replies: 22
Views: 6522

Re: D-50 sounding distorted, noise & creaking

Here, a similar problem is described and solved. Hope it helps. http://forum.vintagesynth.com/viewtopic.php?f=5&t=78276#p741443 Thanks Mooger. I've been following this thread. I got the reverb and SRAM ICs out of the PCB today. Put it back and did a good check on pads and traces. All 100%. Just wai...
by gkmaia
Fri Dec 21, 2018 8:28 am
Forum: HELP!
Topic: D-50 sounding distorted, noise & creaking
Replies: 22
Views: 6522

Re: D-50 sounding distorted

The DAC is actually in two parts, a 16 bit DAC and a ladder DAC for the other 4 bits (20 bit in total). You'd need to check the components in the ladder DAC. I may have found the source of my problem but I don't actually know how to pin point it. If I edit a patch and change the all chorus balances...