HRDx to ODS Conversion... Help Please!!

[wolfiesays]

Yeah,
Even though it appears your footswitch jack is insulated from chassis, it looks like that one solder joint on the "left" where the grey wire leads, could be grounding it to chassis at that point. Check that ground as previously said.

-wolfie

p.s. And guys a heads up I am getting into this project myself and trying to do as much wiring as I can myself before I have a tech. Instagram is a good stomping ground to research for techs who seem transparent with their work.

I thank you all for great pictures for proper lead dressing and wiring of the board in this forum. Thank you all!

[jinx1499]

Hi there,
Starting to figure out whats going on ....sort of. Can some post a nice pic of how the footswitch is supposed to be wired? When I plug in a cable to the footswitch, it goes right to the OD and I can't change anything via footswitch. The Middle was hard wired to the C26 cap and the grounded to CCW of the bass in conjunction with the bass wire that goes there. I can't get the PAB to work at all, but I'll be trying more tomorrow.

[jinx1499]

Oh and also....the difference between the HRM and non HRM volume is pretty drastic. Is there a way I can level those out??

[JazzGuitarGimp]

Hi Jason,

I am in the process of doing a layout drawing for this amp. I have attached an in-progress pdf, that shows the Foot Switch Jack wiring.

The volume difference between Jazz and Rock position is drastic, and this is just the nature of the beast.

The effect of both the Bright Switch and the MID Boost Switch is most obvious in Jazz mode. Please check.

For PAB, this will be most effective with Trimmer Resistor VR8 all the way down (counterclockwise).

Does your footswitch have two switches? Does it have LED's? Does it have a TRS plug?

Ciao,
Lou

[jinx1499]

Outstanding! That will make a world of difference!

[JazzGuitarGimp]

Hi All,

Long overdue, but finally done. Here is the HRD2ODS, Rev B Chassis Wiring Diagram. Please let me know if you spot anything fishy. This is my first drawing of this kind.

Many thanks,
Lou

HRD2ODS, Rev B Chassis Wiring Diagram.pdf

[pompeiisneaks]

I'm looking it over. The only major issue I had on mine was the first input grid was too close to the OD tube causing a lot of noise in OD I swapped mine to pin 2 instead of pin 7... but that's the only thing I'd call out.

~Phil

[pompeiisneaks]

Two other suggestions:

1. yellow on those leads is pretty hard to see for me? maybe darker color?
2. it might be good to have some specifications around 2vs4 power tubes and the board connections etc?

~Phil

[martin manning]

Lou, I would refer to the ODS layouts, 124 say, and rearrange the preamp tube socket wiring to be as close to that as you can get it. Definitely bring the grid wire from the input jack around to the other side of the V1 socket. Consider rotating the sockets 180 degrees and running the filament leads to 4 and 5 through the gap. Standard colors are blue for plate. green for grid, and yellow for cathode. I agree the yellow would be more visible if it were a little darker (a bit more towards orange).

[JazzGuitarGimp]

Phil, Martin,

Thank you both. Doing the layout drawing was an eye opener. In retrospect, I should have done it first. I learned so much about the process along the way. I will definitely be making a few changes for the next revision.

Cheers,
Lou

[talbany]

Personally I would axe the screw terminal connections (you're asking for trouble) and go with the solder especially on the pre-amp side. Make it as fool proof as possible.

Tony

[Dexter.Sinister]

I'm not suggesting it's good practice to discharge with a bang. However, I've never heard it's bad for the caps, either. References?

A BSEE client told me this.

Yeah, a bleeder discharges smoothly without fireworks.

I have a hole in my left index finger from discharging filter caps through my ill placed digit. The bleeder makes is slower and less dramatic.

Safer.

But yeah, shorting with a screwdriver is the OG approach. I changed it out.

[Chris Brown]

Personally I would axe the screw terminal connections (you're asking for trouble) and go with the solder especially on the pre-amp side. Make it as fool proof as possible.

Tony

Solder for peace of mind. I did the screw terminals and it's the only amp I've ever built that I worry about. It's been 3 years with no problems and I've probably taken it out to 50 gigs, but it still bothers me.