1176 MC77 MC76 Meter/Power Switch

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T1M0N_5

Member
Joined
Apr 24, 2009
Messages
9
I'm feeling stupid to ask this, but I am a bit confused.  :eek:

What exactly are the four pushbutton switches on the right of the meter supposed to do?
In the MC77 I thought the first one selects between GR and Level Metering, the second one between Input and Output Level Metering, the third one sets the unit to hard bypass (input directly to output) and the fourth powers the unit on or off.

In the 1176 it seem like it's GR metering, output level meter -10, output level meter +4, off (I suppose meter off, not the wole unit power off).

I have in front of me two MC77 kits (i know, they have been lying unassembled for much too long) and one hairball 1176 REV A/D kit with mnats rev A board. With the two MC77 kits came four identical pushbutton switches like that one:
http://hairballaudio.com/shop/product_info.php?cPath=22&products_id=30

with the rev A/D kit, as we can all see, came one of those above and one of these:
http://hairballaudio.com/shop/product_info.php?cPath=22&products_id=55

So the first confusion is, for the 1176, where the switch should turn the meter of, I have a special 240V switch, while for the MC77, where that would make sense (because it switches the power) I only have those normal switches. The second confusion is, that like with the ratio buttons, they are all interlocking (I hope that is the right word), meaning that even the power switch turns off when I change the metering settings. Is it supposed to do that, because it doesn't seem practical.
In mnats power wiring tutorial the Power transformer wires directly to that switch, so here it switches power, not meter off. But wouldn't the unit power down everytime I change Meter settings (except when I hold the power button while switching)?
http://mnats.net/1176_reva-d_hairball_wiring_power.html

Obviously I have never worked on a "real" 1176 or mc77, so I don't know how this should work. I'm sorry if this was already discussed, I did some search but couldn't find answers. Any help would be appreciated. Thanks, Timon
 
this is correct:
In the MC77 I thought the first one selects between GR and Level Metering, the second one between Input and Output Level Metering, the third one sets the unit to hard bypass (input directly to output) and the fourth powers the unit on or off.
the selected meter mode is independent of whether the unit is turned on or off.  this was necessary to include the input and output metering as well as the bypass without adding extra buttons.

this is not:
In the 1176 it seem like it's GR metering, output level meter -10, output level meter +4, off (I suppose meter off, not the wole unit power off).
it is not just meter off, it turns the whole unit off; that's why power is wired to the OFF switch as in mnats' guide.  the interlocking just means that you have to pick a meter mode for the unit to be on...  when you press the OFF button all meter modes are de-selected and the unit is turned OFF.  i think you are imagining the OFF button backwards -- when it is pushed in, all the other buttons are out and the unit is OFF.  pushing any of the meter mode buttons pops the OFF button out and the unit is on.

as for the differences in the power switches, current mc77 units use a 240V switch like the one in the hairball kit.  the switch you have will work fine.

ed

 
edanderson said:
i think you are imagining the OFF button backwards -- when it is pushed in, all the other buttons are out and the unit is OFF.  pushing any of the meter mode buttons pops the OFF button out and the unit is on.

Yes exactly, you are right, that's where I was thinking wrong. Thanks for clearing that.

edanderson said:
as for the differences in the power switches, current mc77 units use a 240V switch like the one in the hairball kit.  the switch you have will work fine.

ed

Thanks very much for your answer!
Timon
 

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