HRDx to ODS Conversion... Help Please!!

[JazzGuitarGimp]

Any voltage over ~20vDC will give a good SNAP if discharged across a low resistance path like a probe or screwdriver.

I have heard this is unhealthy for electrolytic caps, so should be avoided if possible. It’s always best to bring them down with a resistor in the range of 200k to 470k, 2W.

[xtian]

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?

[JazzGuitarGimp]

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.

[jinx1499]

Spoke to my amp tech today, gonna take it in again with the new instructions. I'll keep everyone posted. Thanks again for all the help, hopefully we'll call this a wrap after this next visit.

[wolfiesays]

Is your tech putting in 6L6 or 5881's? interested in your build progress. Hope it works out for you, it also might be helpful to print out the images here so your tech can see those for reference.

[jinx1499]

Hey All,
Just got it back from the tech:
The good news is it works and it sounds very nice.
The bad news is the the PAB and Mid Boost cannot be used by the footswitch, only by the toggles on the amp. Also, neither the bright cap nor the mid boost are different enough.

This is bittersweet. I'm happy the amp functions and that it sounds good but it's a real bummer that I can't control really anything but the OD switching via the footswitch. I don't know what to do.
He did put 6L6s back in after I spoke to him about what everyone's concerns were.

I can take pictures of the board and wiring for the switches if anybody wants to take a look but you guys have helped so much already, I'm reluctant to do so.
Sincerely, thanks to everybody who threw in their words of wisdom to guide me along. It's made a world of difference.

[JazzGuitarGimp]

Yes, please post pics of the switches; as well lit and as close up as possible. I am sure these issues are caused by miswiring.

Also, it would be nice to see a straight-on, clear view of the footswitch programming jumpers.

Ciao,
Lou

[pompeiisneaks]

I definitely got mine working fine. The pab and od are set on my jumpers to the footswitch and both work independently and great.

As for the third, mid boost, the TRS jack only supports switching two things, so that's what the jumpers are for, you choose which one is tip, which is ring, and the third can only be controlled by the panel switch. As for the bright switch or the mid boost, some of that depends on other variables, like the guitar. a bright switch won't seem super audible on humbuckers but is pretty obvious to me on single coils. It's too harsh for me to even use on a strat with the neck pickup.

What was the bias with 6L6's I think you may need to adjust the bias resistor if you're using 6L6, because the bias was set for the default 5881's and as I recall they tend to run a bit different than the 6l6's.

~Phil

[didit]

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.

Consider the ESR and resulting heating from instant surge discharge.


Best .. Ian

[jinx1499]

Ok, here are the pictures. Let me know if you need other angles or any questions answered.

https://drive.google.com/drive/folders/ ... sp=sharing

[JazzGuitarGimp]

Ok, here are the pictures. Let me know if you need other angles or any questions answered.

https://drive.google.com/drive/folders/ ... sp=sharing

Jason,

Wow, there is so much going wrong here, I don't even know where to start. If it had not occurred to you by now, you might consider the possibility that your tech is not the right person for this job, and that is the kindest way I can say it, and I won't speak of this again...

Here are my initial observations:

- The Master Volume control is bypassed at full on (white jumper at connector VR5 MASTER VOLUME. Get this connector properly wired to your Master Volume pot with a shielded, twisted pair cable.
- The PAB switch is not working because only the red wire goes where it should. The green wire, which goes to some unknown place, should be in the same connector, but the other screw socket, as the red wire (P7 PAB SW). Disconnect the other end of the green wire, then cut its length to get it to the P7 connector, strip and tin the end, then screw it into the point right next to the red wire.
- I see more wires soldered to component leads. In this case, it looks like two shielded cables soldered to the leads of capacitor C26 (Right behind the TREBLE pot connector. I will say it again: THERE SHOULD BE NO WIRES. CONNECTED TO THE BOARD BY SOLDERING THEM TO COMPONENT LEADS. All wires to the board have a connector location!
- The MID BOOST Switch is not working because there are no wires coming in to the MID BOOST SW connector (labeled SW4). Remove the two coax cables from C26. Use an ohmmeter to find two pins on the MID BOOST Switch that are shorted when the MID BOOST Switch is pulled out, and open when the switch is pushed in. Then solder wires to these two points on the switch, and screw them into the two positions on the SW4 connector.
- It looks like the FOOT SWITCH Jack is wired correctly. However, I cannot tell if it is grounded. Use an ohmmeter to measure for a short from chassis to the white wire on the Foot Switch jack and report your findings.

My suggestion is get all of this stuff taken care of, then you will be in a position to reassess what is working and what is not.

Lou

[xtian]

Wow, there is so much going wrong here, I don't even know where to start. If it had not occurred to you by now, you might consider the possibility that your tech is not the right person for this job, and that is the kindest way I can say it, and I won't speak of this again...

Had to be said.

[jinx1499]

Thank you for taking a look. I will sort some of that out and report back. I appreciate your candor regarding the tech and unfortunately, I feel similarly... at least for this project. Some people are too concrete of thinkers,forgetting about the flexibility that is needed in situations like this and I think that's where this all went sideways. Anyhow, I will start looking at those areas and see what can be made of it all.

[pompeiisneaks]

Another way to think of this, is that Lou and Aaron designed this to have a one to one connection off the board in precisely the spots they've designated, but somehow at random there are connections in locations they shouldn't be, as well as what appears to be major confusion about pot wiring etc. I would try to take it one component at a time, and ensure that any wires that lead to/from that component are well understood and only connected on a 1 to 1 basis exactly how the board silk screen designates them.

~Phil

[beasleybodyshop]

In situations like this, I like to print out a schematic or layout and take a highlighter and physically check each connection and highlight it as I go. Done in this way, you should be able to Audit, or Validate each connection and get well on your way to having an amp that works properly.

Also, and I hate to point it out, but some of that soldering work is not that great. I would perhaps look for another tech. Or someone who is more experienced.