Music Man HD130 Reverb Issue (Reverb button not working)
adam79
stopped working. I'm thinking that the wire might need to be replaced.
What type of gauge wire should I use? Also, if it turns out not to be
a bad wire or connection issue, what would be the next thing to check
out? The tremolo button still works, if that matters..
Thanks,
-Adam
Morris Slutsky
> The reverb button on the reverb/tremolo pedal of my Music Man HD130
> stopped working.
Sorry to hear that. The reverb still works when you unplug the
footswitch, right? Otherwise it wouldn't be the footswitch at fault,
it'd be the amp.
> I'm thinking that the wire might need to be replaced.
> What type of gauge wire should I use?
Whichever gauge fits the switch terminals most easily? I keep 22
gauge for most generic uses.
If you suspect the footswitch's attached cable, that's reasonable.
I've often had them go bad right near their connection to the
footswitch box. If that seems to be the problem, you can just remove
the solder joints, cut 6-8 inches off of the cable, strip the jacket
and the wires, and put them all back in the same spots.
> Also, if it turns out not to be
> a bad wire or connection issue, what would be the next thing to check
> out? The tremolo button still works, if that matters..
The switch itself. Use an ohmmeter and make sure it goes off and on
like it should. Actually you should test this before you start
suspecting the wiring.
>
> Thanks,
> -Adam
adam79
> On Oct 13, 11:54 pm, adam79<79ada...@gmail.com> wrote:
>> The reverb button on the reverb/tremolo pedal of my Music Man HD130
>> stopped working.
>
> Sorry to hear that. The reverb still works when you unplug the
> footswitch, right? Otherwise it wouldn't be the footswitch at fault,
> it'd be the amp.
>
I haven't tried any troubleshooting yet; I figured I'd ask for some
suggestions here first. Both reverb and tremolo work on the amp. I'll
try disconnecting the pedal and let you know what happens.
>
> The switch itself. Use an ohmmeter and make sure it goes off and on
> like it should. Actually you should test this before you start
> suspecting the wiring.
>
I only have a multimeter. Would that be any use in this situation? I'm
not that familiar with electronics, but I have enough common sense to
check basic things; I know what I don't know (and what not to touch).
Thanks,
-Adam
RD Jones
> I only have a multimeter. Would that be any use in this situation?
Yes, the HD130 has the Fender style basic footswitch, no lights or
LEDs
on the switch to complicate the circuit. So it's just plugs, wires and
the
switches. Check for a fully open circuit when the switch is off and a
(nearly) complete short when the switch is on.
Also, when the switch is "on" (closed) the reverb signal is being
shorted
so it's off.
One more note is that the MM switch has what looks like zip-cord but
it's actually 2 coaxially shielded cables, one for each function.
> I'm not that familiar with electronics, but I have enough common sense to
> check basic things; I know what I don't know (and what not to touch).
It ALWAYS bears repeating for anyone new reading this ...
MusicMan amps have very high (deadly) voltages present in the chassis.
All tubes amps have for that matter, it's just that MM are some of the
highest.
(over 700 volts)
rd
(former MusicMan authorized tech)
greas...@hotmail.com
Unplug the foot switch from the amp..Using the meter's ohms
function...touch one lead to the tip of the switch cable and the other
to the barrel of the plug. It should make the meter either not move or
move to nearly full scale. Click the foot switch and test the plug
again. You should get the opposite reaction. If the plug has two
separate rings at the top of the plug, check them both and report back
with results...
adam79
pedal backing and everything looked in order. I then tried the pedal
with the rubber part off (to see if I could notice anything happening
when I flicked the switch, and it randomly works now)! I put the rubber
backing piece back on, tried it on the high and low power settings, as
well as the different jacks, and everything works perfectly. Weird, huh?
Lord Valve
No, not at all.
You have a bad solder joint, an intermittent switch,
or - most likely - there is a broken wire in the
cable which makes intermittent contact depending
on how the cable is flexed at the time. This will be
located right at (or very close to) the strain relief
bushing where the wire enters the housing. The
fix (and if you don't have a bad switch or a bad
joint, it will *indeed* be the fix) is to chop the
wire off about six inches prior to the strain
relief bushing, pop the bushing out, clip (do
*not* de-solder) the wires off close to the
switch terminals, strip and prep the cable,
feed it through the hole (don't put the bushing
in yet) and solder the wires to the proper
terminals. (You, uh...you DID draw a diagram
before you cut the harness off...right?) Once
you have everything soldered up, you can
connect an ohmeter to the connectors on
the amp end of the cable and confirm proper
wiring and switch operation. And this assumes,
of course, that you've examined the connectors
for bad solder, bent pins, dirt, corrosion, etc.,
before cutting or soldering anything. Also examine
the cable over its entire length, looking for cuts,
abraded places, or "stretched" looking regions.
Once you're sure everything's tight, you can install
the strain bushing on the cable and push it through
the hole in the housing. It's done this way to ensure
that there's some slack in the internal wiring, which
will be beneficial for the solder joints on the swtches.
See below for snide comments from "RS" (not
his real name).
Lord Valve
Expert (please obsess)
RS
<detr...@ix.netcom.com> wrote:
...[snip]
>See below for snide comments from "RS" (not
>his real name).
>
>Lord Valve
>Expert (please obsess)
Have I been on your mind that much? Why do I need to comment on this?
I think you're capable of fixing a cable. Probably a switch. Stay on
this one!