DH 150 head. Help needed

Brentrocks

Hi all! I just bought a 1980 HD 150 head yesterday.

Everything works great except for the phaser.

It appears that the push pull pot in the phaser control might be bad?

Has anyone else ever experienced this problem?

Where would I find one there’s oddball pots?

Thanks!!!!

Brent

Full Name
brent henderson
Music Man Equipment
HD150 head

Member for

3 years 10 months

Brentrocks Sat, 02/27/2021 - 06:14

Here is a gut shot

Images
Full Name
brent henderson
Music Man Equipment
HD150 head

Member for

3 years 10 months

Brentrocks Sat, 02/27/2021 - 06:25

The pot in question

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Full Name
Lars Verholt
Music Man Equipment
HD-130 head, 210X cab, 210RH cab, RD-50 110 combo, Sixty-Five 112 combo, RP65-112

Member for

10 years 9 months

lmv Sun, 02/28/2021 - 13:54

Hi Brent,

what is the specific reason that you think the pot or the pull switch is the issue?

Does the phaser work if you short the pull switch pins? Do you know if the oscillator works?

Cheers,

Lars Verholt

Full Name
brent henderson
Music Man Equipment
HD150 head

Member for

3 years 10 months

Brentrocks Mon, 03/01/2021 - 04:06

The rotary works on the pot. When I pull the pot out I get phase. When I push it back in it goes away

Full Name
Lars Verholt
Music Man Equipment
HD-130 head, 210X cab, 210RH cab, RD-50 110 combo, Sixty-Five 112 combo, RP65-112

Member for

10 years 9 months

lmv Sun, 03/14/2021 - 16:01

Sounds like the pot was replaced by one that has the opposite switch operation of the original. It's supposed to break when pulled, but it would appear your pot makes when pulled. So it's either living with that peculiarity or replace the pot with the correct one.

Cheers,
Lars Verholt

Music Man Equipment
MM 2-10-65

Member for

10 years 9 months
Profile picture for user mm210

mm210 Tue, 03/16/2021 - 07:20

Personally, I would PREFER that it be off with it "IN". JMHO. Mike.

Full Name
brent henderson
Music Man Equipment
HD150 head

Member for

3 years 10 months

Brentrocks Tue, 04/06/2021 - 09:03

The oscillator does not work.

When I pull the pot out and push it back in, it oscillates 1 time and stops.

I think I confused you with my previous post. The phase does break when pulled.

Do the black LED things on the circuit board control the oscillation?