Pitch Control (non-existent) on Etherwave

Posted: 7/22/2017 9:54:10 PM

From: Columbia, SC

Joined: 7/22/2017

Hello.  I've lurked here a bit, but never posted until now. I just finished 'construction' (not much to it, really) of the Moog Etherwave, and have been testing this afternoon.

Volume antenna appears to be fine.

Pitch antenna does *almost* nothing.  The pitch rises about 40-50 cents when I touch the antenna, but otherwise, the pitch emitted is constant.

To anticipate a few questions, perhaps:

  • finish on the case is just boiled linseed oil.
  • testing did occur in a place not near metallic objects
  • I tested the path to ground (with a Voltmeter to measure resistance) along spots that I soldered, and all seems fine
  • path from the antenna to the solder point on the board ("CH3 to antenna") is fine.
  • all knobs seem to be doing what they are supposed to be doing.  Adjusting the oscillators directly with the 'hex tool' also seems to be having the correct effect in each case.

Anything else I can check?  This is very frustrating...

Posted: 7/23/2017 12:19:28 AM

From: 60 Miles North of San Diego, CA

Joined: 10/1/2014

Hi there,

Check the continuity from the antenna through each antenna coil, the enamel coated wires are fragile.


Posted: 7/23/2017 2:13:10 AM

From: Columbia, SC

Joined: 7/22/2017

Thank you very much.  I will check and report back -- I won't have access to it until tomorrow morning.

Posted: 7/23/2017 2:18:22 PM

From: Columbia, SC

Joined: 7/22/2017

Bingo.  Thank you.  The thin wire of L1 is not connected to the lead.  I missed that the first time -- I think I was pushing the wire back into contact with the lead when testing...

I think I can repair it.  If not, I live close to Asheville...


Posted: 7/23/2017 5:53:33 PM

From: Northern NJ, USA

Joined: 2/17/2012

"Check the continuity from the antenna through each antenna coil, the enamel coated wires are fragile."  - Christopher

Boy are they ever.  Whenever I order these RF chokes they ship all together loose in one bag, rock tumbling from there to here, which guarantees at least one will be DOA with no effort on my part.  Everything else comes triple wrapped in individual anti-static containers that could withstand a direct H-bomb hit, go figure.

Posted: 7/23/2017 8:00:52 PM

From: Columbia, SC

Joined: 7/22/2017

Well, it turned out to be multiple bad points along the way.  The winding wire had come off the leads in three places, and one of them was damaged inside the coil windings as well, which I'm sure was shorting it out.  I `uncoiled' about 20 windings of the damaged coil until I got past the damaged spot and resoldered everything. Big pain in the...  But...it works!  Now for some fun.  And thanks again for pointing me in the right direction.

You must be logged in to post a reply. Please log in or register for a new account.