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andrewb
Copper Member
Australia
19 Posts |
 Posted - 07/31/2008 : 14:35:23
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hello everyone :)
im new here...
i have 5 or 6 boss pedals
they are getting old and having issues one by one...
at the moment my delay DM-2 is giving me trouble
i read around a bit on here and read that the newer and older power supplies are different?
i think i am using a newer power supply,
the LED doesnt light up at all....
and the pedal stays on...
i push the footpedal and nothing happens....
but the guitar is still heard
so first thing i will do is have a try with the older power supply if i can find it.
also i opened it up and ha a look around...
just wondering if anyone else has had a look inside one?
i saw that the wires soldered to the repeat rate knob are different to all the other wires.... it is 3 wires red/white/unshielded wire inside a grey rubber tube..... is that stock?? or has it been replaced?
if it is stock then.... holy crap thats some awful soldering.... 
also the unshielded wire is soldered to the curcuit board but the other end is just sitting inside.... it isnt soldered to anything...
should it be?
one last thing..... where is the ground in boss pedals??
i cant seem to see it touching the casing anywhere....
unless its only touching the casing through the shaft of the input jack plug?
any help and/or pictures would be appreciated....
im fairly new to all this so i am not yet very good at reading schematics....
but im getting there :)
cheers
Andrew
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bossarea
Forum Admin
United Kingdom
3652 Posts |
Posted - 07/31/2008 : 17:03:39
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Have you tested with a battery? It's usually easier to find than an older power supply.
I ran into the grounding problem myself. After I removed the guts from the case I found that some PCB ground points suddenly had voltage. The different grounds (jacks and pots) are connected together through the case. I had to connect a wire between all jacks and pots while working on the pedal. |
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andrewb
Copper Member
Australia
19 Posts |
Posted - 07/31/2008 : 18:51:59
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i gave it a go with a battery
i dont think it worked
so i guess it is a ground issue?
i guess it could of happened when i tightened up the nuts on the pots and jacks?
hmmmm this is so frustrating 
any chance you can give me some more insight into what you did to fix your problems? |
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bossarea
Forum Admin
United Kingdom
3652 Posts |
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andrewb
Copper Member
Australia
19 Posts |
Posted - 07/31/2008 : 21:20:35
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it is soldered to number 13 on my PCB
in the second link you gave me, the very last pic of the dm-1 on that page....
at the bottom of the pic you will see the skinny red and white wires
you can just see the bare wire under the green one.... |
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bossarea
Forum Admin
United Kingdom
3652 Posts |
Posted - 07/31/2008 : 22:32:59
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Aha, that's the shielding on the wire going to the repeat rate pot. The red and the white wires should be connected but the shielding will be connected to the pot ground through the case so it's only attached on one side.
Have you got a multimeter? You might want to start measuring some voltages around the flipflop circuit (Q6 and Q7) to make sure that part works. Since the LED doesn't come on, I'd start there.
Do you have 9V on D3?
The effect is turned on by connecting point 11 to ground. When the pedal is off, collector of Q7 should have a high voltage. When on it should be low. The corresponding voltages on Q6 is the opposite.
Try grounding point 11 manually. If there's something wrong with the switch, then this should turn the effect on. |
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andrewb
Copper Member
Australia
19 Posts |
Posted - 08/01/2008 : 08:04:22
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ok
i just had a play with the old power supply....
pedal powers up....
still no LED on....
and once i pressed the pedal the first time ... it didnt want to work... it wouldnt let me turn it off.... it just cuts out now...
if i jiggle the plugs and power plug it starts to work again....
then when i press the pedal again it cuts out
i do have a multimetre but im not sure how to use it
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Edited by - andrewb on 08/01/2008 08:05:58 |
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bossarea
Forum Admin
United Kingdom
3652 Posts |
Posted - 08/01/2008 : 09:50:23
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It's a tricky one but it sounds like you may have a fault wire or soldering point somewhere.
I would try to poke each wire in turn using a pen or screwdriver covered with electrical tape and see if it makes any change. Have a look at each solder point and make sure the wires are properly attached. |
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andrewb
Copper Member
Australia
19 Posts |
Posted - 08/01/2008 : 10:46:55
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i had a quick check of all the soldering points when i first opened it up....
everything looked decent except for those red and white ad unshielded wires...
is there a way to open up the power socket? it may have rust or corrosion on it?
or i will just try and scrape it off the best i can from the outside...
will also have a check for rust and corrosion on the points inside the input/output sockets....
i will also try connecting point 11 to ground.... see what happens...
i just dont want to fry it
thanks for the help by the way... it is all much appreciated :)
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bossarea
Forum Admin
United Kingdom
3652 Posts |
Posted - 08/01/2008 : 13:58:05
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You might want to utilize your multimeter. See if you can find a setting that displays Voltage. It's got to be direct (not alternating). This is usually shown as -, = or something similar. Alternating is shown as ~. Most multimeters will have different settings like 2, 20, 200 or 2000 for direct voltage. The number is the highest voltage you can measure. For a pedal, the highest voltage is 9V so use the next number. In the example above that would be 20. Test the multimeter first by measuring the battery directly. It should show somewhere between 9V and 10V. Now that you know that it works you can measure voltages inside the pedal.
Look at the schematic and find the arrows pointing straight up. This means you should have 9V on these points. A good place to start is on the diode D3 that is connected to the LED. |
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andrewb
Copper Member
Australia
19 Posts |
Posted - 08/02/2008 : 11:25:41
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well after spending hours searching for my multimetre....
i think some one has taken it
so i had a closer look at the red/white/unshielded wires inside the grey tube......
and noticed that the red and white was melted!
i cut a bit off the grey.... and had a peak inside...
the red and white wires have been melted together....
i guess they were touching?
can i solder on new wires to replace them??
i will just have to take note that i changed those wires incase someone tried to repair it in the future....
is it ok to just solder in the new wires ?
(i knew that soldering looked mighty bad!!!!) |
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bossarea
Forum Admin
United Kingdom
3652 Posts |
Posted - 08/02/2008 : 15:54:53
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| It is fine to solder on new a new wire but try to find one of roughly the same type. If you replace the red/white shielded wire with two separate wires, the pedal could become noisy. The reason the old sleeving is melted is probably because someone has touched them with the soldering iron. |
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andrewb
Copper Member
Australia
19 Posts |
Posted - 08/02/2008 : 19:50:07
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i will give it a go
i found some similar wire..
i will solder it up and give it a test and let you know how i go...
i stil dont know what to do with the other wire just sitting in the case....
oh and i went around and checked that all the wires where soldered in fine... they seem to be alright...
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Laurie
Double Platinum Member
Canada
4854 Posts |
Posted - 08/03/2008 : 14:58:50
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Hi andrewb!!
Can you post pics of the pedal? Both sides of the board and the wiring - looking into the pedal towards the jacks and back of the switch?
Regards,
Laurie. |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 08/03/2008 : 15:18:17
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Hi andrewb
Welcome to the forum from Australia.
As Laurie has requested, please upload some pictures.
How come it stopped working?
Can you recall what might have happened to it just before it went fauty?
Regards Dr. Bob |
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andrewb
Copper Member
Australia
19 Posts |
Posted - 08/04/2008 : 09:56:44
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im from australia 
i will get some pics... but they wont be great... have to be taken with my mobile phone...
my father had a gig about 3 months ago... that was the last time it was used....
between the gig and now... it has been dropped... and thrown around a lil in the car... thats about it....
just been sitting on my floor with my other pedals since....
may have been hit with a vaccume... my mother is good at hitting my guitars and things with that bloody vaccume 
a week or so ago.... just before i posted this topic...
i picked it up and the pots were moving around and so where the input/output... thats when i decided to tighen them up and clean up my pedals...
they had a serious amount of dust and grime on/in them....
i took the repeat rate pot out a few days ago as i was going to resolder the red/white wires..... (but im sick at the moment so wont be doing that for a while)
and around the hole was a ring of dirt....
someone said that it is all grounded through thw case/pots/jacks?
could that layer of dirt/grime be affecting that?
i scraped it off anyway.....
havnt had a look uner the other pots...
scraped it off from around the jack holes too though...
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Topic |
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DM-2 problems
