#124 Questions

[norburybrook]

Having built a bluesmaster HRM a few years ago with left over bits and pieces into a cut down chassis with the only thought of just making things fit regardless of where they were, it turned out to be a great sounding amp so I wouldn't sweat this stuff, just build it



M

[Bombacaototal]

Thanks Marcus, wise advice as always. I have drilled as per Two Rock / Taylor

[Bombacaototal]

I will go back to the low plate skyline 124 soon and just wanted to double check something. The bass pot without the Rock/Jazz and without the relay is wired as follows: bass right lug connects with the treble left lug and 0.1uF on the board and there is a jumper from the middle lug to the right lug, correct?

[Bombacaototal]

A quick question for you regarding the mounting of the Power Transformers.

Do you guys remove the outer metal washer of the long screws and then sandwich the chassis in between?

Or do you leave the transformer as received (incl the outer metal washer) and then add an extra metal washer on the inside of the chassis?

[sluckey]

It's called a nut, not a washer.

That's part of the transformer. You need four extra nuts to bolt the transformer to the chassis.

[Bombacaototal]

It's called a nut, not a washer.

That's part of the transformer. You need four extra nuts to bolt the transformer to the chassis.

Thanks for correcting me, indeed a nut

Noted with thanks regarding the need for extra ones to bolt the transformer

[norburybrook]

It's called a nut, not a washer.

That's part of the transformer. You need four extra nuts to bolt the transformer to the chassis.

Steve,

Interesting, I've been removing the nut and mounting the transformer directly on the nylon washer then attaching the nut on the inside of the chassis.

Is this 'wrong' in a mechanical,electronic way?


M

[Bombacaototal]

It's called a nut, not a washer.

That's part of the transformer. You need four extra nuts to bolt the transformer to the chassis.

Steve,

Interesting, I've been removing the nut and mounting the transformer directly on the nylon washer then attaching the nut on the inside of the chassis.

Is this 'wrong' in a mechanical,electronic way?


M

Hi Marcus,

I was working on the amp at 2am and brain was drained but in the morning I reverted back to the spec sheet of the PT and they specifically mention not to remove the nut (attached)

I wonder as well in mechanical or electronic way what is the impact of not having them there.

Rafael

[norburybrook]

well having the nut will raise the cover off the chassis which might have some decoupling effect??? the transformers I use have nylon washers so they would have the same effect possibly.

Don't know, I'm interested in the replies from those more knowledgeable


M

[Bombacaototal]

well having the nut will raise the cover off the chassis which might have some decoupling effect??? the transformers I use have nylon washers so they would have the same effect possibly.

Don't know, I'm interested in the replies from those more knowledgeable


M

Hi Marcus, mine had 3 nylon washers and 1 star washer. I am interested on replies too.

[Guy77]

In my last several builds using hammond power transformers I have left on all the washers and nuts that came with the original transformer and added 4 extra keps nuts to mount the power transformers to the chassis . At first I thought taking off the nuts would better help to transfer heat but there was no noticeable difference in heat with nuts on or off.

No issues on these builds using this method so I guess I am sold on it.

Cheers
Guy

[Bombacaototal]

I just wanted to double check if my DPDT 3-way switch (ON-OFF-ON) for the bright is wired correctly.

The drawing below is the tonestack minus the relay boards.

Many thanks!

[pompeiisneaks]

My general understanding is that the nuts are tightened by the manufacturer to ensure the laminations are at the right compression. Loosening them can decrease the performance of the transformer, causing problems. Thus why it's best to leave the manufacturers as is, and add new ones for your mounting needs.

[Bombacaototal]

Question about wiring the PT. If the Green/Yellow wire (marked on the attachement) is internally grounded, should I just leave it asside (maybe headshrink the lead and let it sit there?). Or do I ground it again

[martin manning]

I would ground it near the PT, which will insure that the transformer's core is well grounded to the chassis.