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svengali
Bronze Member
Australia
111 Posts |
 Posted - 02/03/2009 : 22:49:40
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hello all,
i have been given a bf 2 ss screw pedal.
it doesnt work..sort of.
id like to fix the bastard, but i need some help y'all.
when used with the correct adaptor- aca- several different things can happen.
1. when activating the pedal with the switch, the led comes on, but fairly faint and with no effect apparent.
if i then press the pedal again, the led gets brighter,possibly too bright, and the effect works, and works well.
then, when i press the pedal to turn the pedal off, it wont turn off.
the led remains on, and the effect continues.
pls note here that i am operating the switch manually with the lid up so as to make sure the switch is being tripped.
2. when used with a battery, when activated, the light comes on, at what i consider the normal brightness, and the effect works.
but it wont turn off.
3.on occasion, as soon as the guitar cable is plugged in, the led is activated and the effect is activated without pressing the pedal.
again, the effect cannot be turned off normally.
4. on occasion, the pedal can be turned off by pressing the pedal, however on those occasions the pedal does not work normally as you have to press the pedal twice as described in point 1 to activate it.
5. on occasion, the pedal cant be turned on by any method.
6. the pedal has at some stage been partially submerged in an as yet unidentified liquid..beer?
the outer traces of the board have darkened, on the lacquer side, and there is some kind of residual green oxide? on some of the component legs associated with that outer part of the board.
this isnt too bad actually and could be cleaned right up id suspect.
7. ive tried hot wiring the switch to no effect (using a jumper).
8. at no time does the signal from the guitar not go through the pedal
9. there are no broken wires or burnt components..i have carefully checked for this.
10. this pedals behaviour is unpredictable and frankly i will not impose a non-custodial sentence as its behaviour could upset the emotional integrity of any further users.
Boss jail?
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 02/04/2009 : 13:48:53
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Hi svengali
What level of technical & soldering-desoldering skills do you have?
It will help us know what level of testing & repair, we can help you out with.
And remember that the SS vintage BF-2's, were 12V unregulated ACA power supply type pedals.
Regards Dr. Bob |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 02/04/2009 : 13:55:32
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quote:
7. ive tried hot wiring the switch to no effect (using a jumper).
Do not leave a shorting link permanently across the switch, it will mEga COnFuSe the flip-flop. 
The switch is only a momentary type, NOT a toggling type.
Regards Dr. Bob |
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svengali
Bronze Member
Australia
111 Posts |
Posted - 02/04/2009 : 21:07:59
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thanks dr bob.
i solder all the time, i repair and make old tube amps.
i have changed chips a couple of times in these pedals..fiddly but no problems.
im pretty good with a multimeter and i also have a bf2 ss that is in great shape which i could use to compare.
regards
svengali |
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svengali
Bronze Member
Australia
111 Posts |
Posted - 02/04/2009 : 21:28:26
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dr. bob,
sub plot.
the serial number on my functional bf 2 ss is 0400.(first three months of production)
it is not momentary led, and the board looks virginal, there are no new solder looking bits or jumper wires.
the way the non functional pedal behaves also makes me feel as if it isnt momentary led...its serial number is 050800.
regards svengali. |
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svengali
Bronze Member
Australia
111 Posts |
Posted - 02/04/2009 : 21:53:47
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i see now that you meant momentary switch, not momentary led.
yeah. |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 02/05/2009 : 08:20:50
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Hi svengali
Check the continuity of the disco loured tracks.
They might have been eaten away by whatever is in the liquid.
Have any of the components been severely corroded by the Mystery liquid?
Try clean it up a bit with a brush & some PCB cleaner.
If you don't have any type of PCB cleaner.
Go & do this outside, in a well ventilated area.
And don't smoke.
Use some clean Methylated spirits, Metho.
- White Lightning 
Use the Metho & brush to clean off the whatever crud.
leave it to evaporate dry.
Now:
Use your known good BF-2, as a static comparison.
BTW - please tell me-us more about your tube amp build/rebuilds.
Regards Dr. Bob |
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svengali
Bronze Member
Australia
111 Posts |
Posted - 02/05/2009 : 09:44:43
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will do dr bob...ill give a full report after cleaning tracks.
amps..tubes...i love em.
It all started years ago when my fender bandmaster popped a bias cap.
I had absolutely no idea.
Of course, after being pointed in the right direction, i had to find out what a bias circuit actually does.
one thing led to another....
now, that bandmaster has a 300 milliamp ht ---9 amp filament voltage power transformer out of a 1965? television...
and four 6v6gt's - they are actually 7c5's that utilise a loctal socket...(shhh)
also, i put tube reverb in it.
that bandmaster is an amazing sounding bit of kit.
i own a plexi clone that i made using old australian transformers and mercury magnetic stuff and stuff from george metropoulos in the usa.
the box for that amp is actually the remnants of an as yet unidentified clone kit produced locally---20-30 years ago?
this plexi clone to my ears sounds exactly like led zepps physical graffiti..awesome but too loud for any thing more than recording.
i play in a band where ive made all the guitars..and most of the amps.
word gets around, i do repairs on peoples amps all the time..usually for free.
amps are easy.
but, they'll kill you in a heartbeat.
I have an eminar amp that runs six el34 tubes with a plate voltage of 640 volts.
i have some transformers that put out after rectification...2500 volts.
actually i have some very large submarine transmitting tubes to suit those voltages and one very large output transformer with the correct impedances..
old amps can be easily and quickly fixed...most times.
scope? nah...
ic's..?..nah...
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svengali
Bronze Member
Australia
111 Posts |
Posted - 02/06/2009 : 07:06:50
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update
ive left the pedal on with aca adaptor ( effect actuated) for about
48 hours.
this seems to have fixed it..id guess temporarily...
the pedal works just like it should.
smacks of dried electrolytic cap.
ill change all the little bastards.
these cap issues are going to come up more often i reckon.
ill also metho the board.
svengali. |
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starr36
Platinum Member
Canada
1172 Posts |
Posted - 02/06/2009 : 08:18:42
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quote:
Originally posted by Dr. Bob
Hi svengali
...
Go & do this outside, in a well ventilated area.
And don't smoke.
Use some clean Methylated spirits, Metho.
- White Lightning
...
Regards Dr. Bob
Not at all meant to Hijack ... bud Dr. Bob, did you goto Woodstock? |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 02/06/2009 : 10:20:35
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Hi svengali
It's better, if you can go to Dick Smith, Laycar, Altronics,
or whatever electronics supplier & get some PCB flux residue cleaner in a can.
I use Electrolube FLU "FluxCleane". the one with the stiff nylon brush on the spray head.
It works very well, sells for around $20au a 400ml can.
Most people have access to Metho, & I tend to use it as a last resort - or poor mans cleaner.
Metho. is highly inflammable, so please take care in it's use.
But it works fairly well.
And make sure it has fully evaporated off the PCB's before use.
It's good news knowing that your SS BF-2 is working.
......
Some of your tube restoration & builds sound very exciting.
Last tube build I made was my 63-65 Fender Brownface tube preamp, for my Mesa 50-50.
I built it with a full complement of the older Fender Tone stack,
I used a voltage quadrupler to get my plate voltages.
It works very well, & makes the Mesa really sing.
I still work on a few tube amps now & again.
But man, they seem to be getting heavier & heavier, every passing year. 
Regards Dr. Bob
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starr36
Platinum Member
Canada
1172 Posts |
Posted - 02/08/2009 : 08:43:50
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| its not an easy thing to just "figure out tube amplifiers" so that was interesting to read of you your adventures, svengali. there is only one rule in working with amplifiers (or most electronics for that matter) - KEEP ONE HAND IN YOUR POCKET! |
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svengali
Bronze Member
Australia
111 Posts |
Posted - 02/08/2009 : 09:51:47
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dr bob.
is that brownface preamp the one with the true pitch vibrato?
my friend has a brownface something or other with the three tube
vibrato, and it sounds absolutely amazing.
It would be very easy id think to tap the signal at the
appropriate place and re inject the effected signal at the correct
juncture?
True pitch reverb outboard..connected either by effects loop
or 'straight injection'
the mesa utilises effects loop? is it tube effects loop?
I actually have a nos mesa dual rectifier o/t and nos mesa
simulclass o/t. |
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svengali
Bronze Member
Australia
111 Posts |
Posted - 02/08/2009 : 09:53:27
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| true pitch vibrato, not reverb as aforementioned. |
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Topic |
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svengali to mission control- bf 2 problems
