Messages

[Console Repair/Mod Center / Re: PC Engine duo RGB audio hum/buzz]

Well,specifically is was referring to the high frequency interference heard when playing games like bomberman '94, ninja spirit,son son 2 and many others, its like a whine or something
I tried hooking up (soldering) the audio cable seoerate to the video direc from din connector to my audio amp and it still there
I tried with a 31 band equalizer but have to really cut nearly all to get rid of it so that it ruins the audio
I think i read somewhere that its caused by thr huc6280 directly

[Console Repair/Mod Center / Re: PC Engine duo RGB audio hum/buzz]

Nobody?

[Console Repair/Mod Center / Re: PC Engine duo RGB audio hum/buzz]

Is there anyone here who has found a way of eliminating or reducing the high frequency whine emitted by the huc6280 chip?
I find that whine really annoying , if the volume is up during gameplay (and heck, it's always up! :-) )..then it is clearly noticable
I am using a decent cable ( RGB-Sync to scart) that does not produce to much hum/buzz but this high frequency whining is terrible

[Console Repair/Mod Center / Re: Pc engine Duo-R one audio channel not working]

issue solved
was cable issue , i inversed 2 wires, the clue i got that led to the solution was from ClodBusted, i was able to trace the channels to the correct pins on the DIN conenctor, there i noticed that i inversed 2 wires, i wonder how i did not see this.. so embarrasing.. i actually made 2 new cables and the one i was using had the issue....

Anyways fixed now and got a completely recaped duo R and even did the jailbar fix so future proof at the least ,so many thanks again to you ClodBusted!

Now on to the next issue, removing the high pitch noise noticed on games like ninja spirit and many others
the high frequency noise seems to be a know issue not only limited to the DUO R , but i have not seen solutions for it

i was thinking of trying something like a high frequency notch filter on the audio channel outputs to filter out  just that offending frequency

To be able to do that i will need to get the scope from work to determine first what frequency it is exactly

[Console Repair/Mod Center / Re: Pc engine Duo-R one audio channel not working]

Thanks ClodBusted!

So it seems pin 17 is left out and pin 18 is right out
At work i have a scope i could use for signal tracing
Is it correct to say if either of these do not output the chip huc6280 is defective? This is where the audio 'starts' right? Before it gets sent to the various preamps and stuff i mean

[Console Repair/Mod Center / Re: Pc engine Duo-R one audio channel not working]

Guys ,

I really need your help with this..
I need to know where i can start to look to troubleshoot this one audio channel that is not working, as i understand after some more googling the HU C6270 is handling the sound but i have no pin out nowhere..
Is anyone here able to point me to a starting point for the audio channel troubleshooting on the duo R?

there are no visible problems, i have done full recap but still the channel does not come up
Where should i start looking
Please?

[Console Repair/Mod Center / Re: Pc engine Duo-R one audio channel not working]

..so far i identified some 'possible' culprits of my failing audio channel but off course i can't know for sure :

Mitsubishi's M51131L (dual channel volume control)
IC's 4558 (Pre-amps) ,there's about 5 of those
one IC 4560 (Dual audio Amp)

The only way i can go at this is to change all these and hope this solves it but i wish there was some other way as this is rather shooting from the hip as i can't know for sure

[Console Repair/Mod Center / Pc engine Duo-R one audio channel not working]

Hi Guys,

One of the audio channels has dropped out on my Duo R..

What i tried so far:
verified cable and measured the pinout from board till scart end of the cable, all good there
Verified cracked solder-joint, all good there
Even went with full re-cap but still only audio through one channel

Both channels worked fine but one suddenly fell out

Any sugestions as to where to start looking?

thanks appreciate all the help i can get with this..

[Console Repair/Mod Center / Re: Duo R suddenly has one of the audio channels completely gone]

Fellows,

Does anybody here on the forum have a schematic of the duo-R i could use to try and figure out why only one audio channel is working?

That would be a great help and would be very much appreciated!

[Console Repair/Mod Center / Re: Duo R suddenly has one of the audio channels completely gone]

Hi everyone,

I am back, today, got the full cap replacement kit for my Duo-R.

So i went and replaced all the caps meticulously
The good news is i did not mess-up my Duo-R, as it still booted perfectly but the bad news is:
Still only audio through one channel..whuuuut??....

I verified my Din8 to scart cable again with multimeter and the sound pins through for both channels starting from the board's audio pins (measured on the board itself) all the way through to the scart end , no problem there so this got me very worried now

Does anyone has an idea what could be causing one of the channels to drop like this? We can rule out the caps now.

[Console Repair/Mod Center / Re: Duo R suddenly has one of the audio channels completely gone]

ok thanks for the advice !, i will take my time swapping them all out, i will post back if it helped or not, for now my DUO R will remain on the repairbench for the cap-kit to come in

Luckely i still go the little white pc engine so hucards are still very much playable for me

i want to thank you again for taking the time to answer me i greatly appreciate the help ;-)

[Console Repair/Mod Center / Re: Duo R suddenly has one of the audio channels completely gone]

That looks very nice :-)
Mine i did myself as well, looks pretty good too, i used an RGB amp from UK with components premounted (was to lazy to make it myself ;-)

The DIN 8 connector pins are all good, no problem there the audio pins measure through from cable to board

I ordered the cap kit but man..i can't say i look forward changing all these caps, it's like a small army of them on the board..i counted at least 70 of them

Just checked and according to wiki, the DUO R is from 1993, that would make these caps are almost 25 years old so i think it's possible some when't bad but I am not convinced however that it will solve the problem but xithout the audio schematics its my only option

[Console Repair/Mod Center / Re: Duo R suddenly has one of the audio channels completely gone]

Hi,

I looked carefully at the soldering done for the RGB mod and everything looks good, no visible cracks in soldering and everything connects through (gnd , 5v , RGB and Csync, no issue there)
None of the caps seem to have 'popped' on top so i need to start looking at the beginning of the audio channels IC's and follow the path and hopefully find it that way but i need some kind of audio schematic for the duo R to be able to do that.

I could go the "change all caps" way by ordering the set from console 5 but i really want to avoid doing that as it seems more a last resort thing as you do not know if it will even fix the problem

can anyone please help me with the audio schematic for the Duo R?

[Console Repair/Mod Center / Re: Duo R suddenly has one of the audio channels completely gone]

Does there exist an audio troubleshoot scheme for the duo-R so i can start at the beginning and trace to the point of faillure, i do have the skills to do that but i need a starting point. :-)

[Console Repair/Mod Center / Re: Duo R suddenly has one of the audio channels completely gone]

Hi Keith,


Yes correct mine is RGB modded with a DIN5 replaced by DIN8, the issue is the same with Hucard and CDROM ,i tried audio CD's as well same issue, only one channel seems to work

@Gtsamour,

When you say capacitor replace, you mean ALL of them or just a specific set controllng the audio?

I also want to say thanks for taking the time to respond to my cry for help! I appreciate it very much as i really am in a pinch here (just got ninja spirit Huecard today and was looking forward to some hardcore gaming..then this issue quickly calmed my joy.. )

[Console Repair/Mod Center / Duo R suddenly has one of the audio channels completely gone]

Hi Guys,

A few weeks ago, i got myself a DUO R system, when it came in everything worked perfect for a couple of weeks, no issues at all.
However, after being able to play fine for a couple of weeks on my system, suddenly, one of the audio channels is completely gone..

I ruled out the cable ,its fine (works perfect with other Duo R at a friend's place) ..i checked the connections on the duo R's DIN8 (mine is RGB modded) but all looks very much in check there too, so i do not know what is causing it or if there is something i could do to fix this.

As a note, I have soldering skills, but i have no idea where to look first for this issue.

Can someone here point me in the right direction with this issue?

Much appreciated

regards,
Edwin