HRM Bypass

[Blindog]

Hey guys,

I've searched for this topic and I've found some posts that talk about this subject but I haven't found what I'm looking for. I seem to remember a post about a switchable HRM bypass that allowed a partial bypass or full bypass. I built a Brown Note Blue Monkey 88 and I'd like to experiment with the HRM bypass.

Thanks!

Mark

[ToneMerc]

My HRM has a pull/push mid pot. pull it and lifts the HRM TS. If I had known I would have preferred that setting so much, I would have put it on relay instead.

TM

[Blindog]

My HRM has a pull/push mid pot. pull it and lifts the HRM TS. If I had known I would have preferred that setting so much, I would have put it on relay instead.

TM

Thanks TM, I'm glad to know you like this mod. I was also thinking about using the push/pull pot. Gotta order a damn pot, nothing in my stash!

Mark

[ToneMerc]

Thanks TM, I'm glad to know you like this mod. I was also thinking about using the push/pull pot. Gotta order a damn pot, nothing in my stash!

Mark

Yeah, the hardest part was finding a full size CTS p/p NC pot of the right value.

TM

[Structo]

Do they make them?

[ToneMerc]

Do they make them?

You can get new CTS push/pull solid in 1M.

TM

[DonMoose]

Do they make them?

You can get new CTS push/pull solid in 1M.

TM

H'bout a relay?

[Blindog]

Do they make them?

You can get new CTS push/pull solid in 1M.

TM

H'bout a relay?

Thought about that, but I don't know how I'd switch it...I'm using the 3 button footswitch with MIDI cable.

Mark

[Blindog]

Do they make them?

You can get new CTS push/pull solid in 1M.

TM

TM, who stocks this? I've tried Mouser, Allied, Digi Key, but I could be missing something...

Thanks!

Mark

[67plexi]

Date code 1984 d shaft http://www.ebay.com/itm/2-Potentiometer ... 339251c5ca

[ToneMerc]

Do they make them?

You can get new CTS push/pull solid in 1M.

TM

TM, who stocks this? I've tried Mouser, Allied, Digi Key, but I could be missing something...

Thanks!

Mark

http://www.tubesandmore.com/products/R-VC1MA-PP

IIRC, the switch on these and most switched CTS p/p pots are NO (normally open) though. A normally closed is what you want for simply lifting the TS. The NO is perfect for a push/pull bright switch or triggering a relay.

99.9 % of sellers never disclose whether the switch is NO or NC.

TM

[ToneMerc]

Date code 1984 d shaft http://www.ebay.com/itm/2-Potentiometer ... 339251c5ca

That's how I have found the ones I have used, scour eBay or surplus shops. I struck out a few times buying blind hoping I would find the right switch config, but luckily these types are relatively cheap and it's a minor hassle to cut down the shafts.

TM

[Blindog]

Date code 1984 d shaft http://www.ebay.com/itm/2-Potentiometer ... 339251c5ca

This one's listed as "pull to open", just what I need!

Thanks!

Mark

*Edit- Just noticed it was linear taper. I was gonna replace my Level pot with this...think it'll be ok?

[ToneMerc]

*Edit- Just noticed it was linear taper. I was gonna replace my Level pot with this...think it'll be ok?

Sure, although if you have coax soldered to the pot back you might have to redo both strands. If not, you are golden.

Also,since it's a D shaft you might encounter a small issue of how the knob set screw will index. I have converted D shafts by inserting a shaft bushing and filling the void with epoxy.

TM

[mhartman]

A little off topic with regard to the pot switching part of this discussion, but, for the curious, here's a shot of how Two Rock did the HRM bypass on the Opal (the switch is the one on the far left in the pic with the coax going to the HRM board).