Hi Greg,
Here¹s a couple of pointers and comments. Please don¹t take offence at any
of my comments, please!
1. Don¹t use second hand parts if you can avoid it! All the trimmers and the
test switch look like transplants. You can easily get new ones off the shelf
and increase your reliability.
2. Ditto with the ceramic resonator
3. Please remove that nightmare of a d/a converter and replace it with an
off the shelf DAC08 or DAC800. There is no reason to recycle this part
4. The two transistors on the far right-hand side look like transplants. The
originals are not pin for pin compatible with this board. Use the parts
stated on the parts list.
5. R83 is missing! This might be your problem!
6. Take the memory out. Carefully tin the legs again with fresh solder. Use
a solder pump to remove the fresh layer and then clean the legs with
deflux-it¹. Reinsert. Much neater job. Work carefully and don¹t apply too
much heat at once.
7. Make sure the top side of CN10 is also soldered as well as the print
lower deck. Have seen issue in this area before!
8. If the problem persists switch the two LM13600 around and see if you have
problems with the PWM functions. If so replace the pair with two LM13700.
Apart from that, good work! Let us all know how you get on!
Cheers,
Andy
On 05/06/2011 01:20, "hotdogfinger25" <gregory.oconnell@gmail.com> wrote:
>
>
>
>
>
>
>
> Hi Andy,
> Thanks for your response! I am wondering if I might have fried IC 33 and 32 in
> the transfer from the old board. Would the D/A problems and the out of control
> MG circuit be related? Sorry if these questions are tedious.
> Here are some macro shots I have uploaded to my photobucket acct.
> Thanks again!
> Greg
>
> http://i960.photobucket.com/albums/ae89/jellocello/p003.jpg
> http://i960.photobucket.com/albums/ae89/jellocello/p008.jpg
> http://i960.photobucket.com/albums/ae89/jellocello/p010.jpg
>
> --- In PolySix@yahoogroups.com <mailto:PolySix%40yahoogroups.com> , Andrew
> Jury <andy@...> wrote:
>> >
>> > Hi Greg,
>> >
>> > You might want to have a look at the values of the components you have used
>> > around the D/A converter section of the board. If you like take a nice
>> > details macro¹ shot of the board and post it where we all can see. I am
>> > sure some eagle eyed person will be able to spot the mistake. The reason >>
one
>> > of the LEDs is stuck on 5 is that the full range of voltages are
>> > unattainable from the D/A converter IC33 over the entire input bit range.
>> > These are checked by the CPU when in test mode.
>> >
>> > Cheers,
>> > Andy
>> >
>> >
>> > On 31/05/2011 23:02, "hotdogfinger25" <gregory.oconnell@...> wrote:
>> >
>>> > >
>>> > >
>>> > >
>>> > >
>>> > >
>>> > > Hello!
>>> > > I recently completed one the KLM367 Clones and the MG circuit is not
>>> working
>>> > > properly. When I turn it on the MG speed slowly ramps up to maximum
>>> speed and
>>> > > the level is stuck on "10" I did all the bug fixes to no avail. The
>>> arpeggio
>>> > > speed is normal. Also, during the calibration found in the service
>>> manual,
>>> > > when you are supposed to make 1 and 8 light up in test mode after
>>> switching
>>> > > the tape enable on, I can only get 1 and 5 to light up.
>>> > >
>>> > > or {2 and 5}
>>> > > or {3 and 5}
>>> > > or {4 and 5)
>>> > >
>>> > > Has anyone else experienced this problem? Thanks! Greg
>>> > >
>>> > >
>>> > >
>>> > >
>>> > >
>> >
>> >
>> >
>> > [Non-text portions of this message have been removed]
>> >
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>
[Non-text portions of this message have been removed]
