HRD plate load resistors, anything else?

[MickeyB]

Have a hot rod deluxe, found bad plate load resistor, was told good idea to replace them all. I plan on keeping this amp for a while and was wondering, Is there is anything else on this amp that I should replace (besides tubes) while I'm ordering parts and taking it apart?

[cminor9]

Smart man, good question.

Replace the Master volume pot with an audio taper. Ever wonder why the drive channel goes from quiet to very loud so quickly? Fender put a linear taper pot in there! Stupid stupid stupid. It's all marketing (so I have read) so that kids go into the music store and are blown away by how loud the
"distortion" channel is on 2 and simply MUST have it cause they think on 12 it'll tear the roof off the place. I'd think the amp's a little too high end for such shenanigans, and it already will tear the roof off at 12. If you use the drive channel, get the right pot for it. The pots are small, so get a mini pot for it (I used a 250k mini pot for a strat). Don't worry about the little wings on the side of the pot. Those just mount it to the PCB and will be a PITA to remove from the PCB. Mount the jack to the chassis and run leads to the PCB. But please double check the pot's value. I only *think* it's 250k.

Also, on my DeVille, the crappy input jack stripped since they brilliantly decided to put a metal nut on a plastic sleeve. That caused many headaches and taught me the importance of having a backup during a gig (so you can guess when it decided to start acting up.) I'd replace all jacks, or at least the ones you use, with switchcrafts. Use shorting jacks (part # 12a) for the inputs. Not sure about the others, since I don't really use them and have not replaced them.

I have had mine for 12 years and counting now, and I don't ever plan on getting rid of it. It's just those two annoyances, the linear taper pot and the cheap jacks. It's also too big and loud, but that's another discussion

If you want to know more about that amp, go here: http://www.studentweb.eku.edu/justin_holton/

[MickeyB]

I did already plan on the pot change (should have mentioned) but thanks for the link for mod ideas.

[mac1amps]

It's really nutty that it took Fender so long to figure out how crappy those jacks are. I've replaced SO MANY of those things at my shop on the Hot-Rod and the "Blues" series Deluxes and DeVilles. I've seen some guys post, that they've replaced them with the old style Switchcraft jacks, but I've been apprehensive to try that due to potential grounding issues. The newer ones SEEM to be better. They're more like "Brit" style jacks, that hold up better (I think they're made of a more "forgiving" hard rubber as oppossed to brittle plastic. They're also made with much wider, more durable threads).
I've also found it to be worthwhile to go over much of the "cold" P.C. soldering, especially at the jacks, the pots, and at those power resistors going to the low voltage supply. It's not uncommon for them to desolder themselves from their own heat.
Also, be sure to keep the contacts clean on the "power amp in" jack (especially if you DON'T use it much), or you'll start to have cutting out issues resulting from dirty/oxidized contacts.

[MickeyB]

Are those new style jacks only available through Fender?

[mac1amps]

Unfortunately, the newer jacks aren't compatible with the older versions of those models. They re-designed the boards differently......figures, doesn't it?

[MickeyB]

Of course. Ah well. If I do wire in the switchcrafts, should'nt I use shielded cable from the jack to the board? I notice online that guys are just using std wire. When I changed the input wire to shielded on my 6G16 build, it did cut some of the noise out, but those were longer wires.

[52 Bill]

...should'nt I use shielded cable from the jack to the board? I notice online that guys are just using std wire.

I think I remember reading somewhere that any open signal wire longer than 2" should be shielded. The wires to the jack will be so short, that it will probably be difficult to use shielded cable there. In any case, the wires are inside the metal chassis and plain wire should be fine.

[cminor9]

Alternatively, you could put some plastic nuts on those plastic sleeves. Maybe not as durable as all metal, but at least you don't have a hard nut on a soft sleeve. That is an invitation for jack failure and I too could not believe that Fender did that. I am no mechanical engineer, but I could easily foresee problems with that setup. Stupid!

I put a metal shorting jack on my HRD and had no grounding problems. I ran very short leads (< 2") to the PCB. The PCB fits very tightly in the chassis, so you don't have to go far from the jack.

I think the only time you'd need to worry about ground loops is if that amp used star grounding. I never took the time to decipher the PCB, but I doubt it uses that grounding scheme. If it uses a normal fender grounding scheme (at least from the old amps) they probably just run the ground to the same place as the preamp. Ok, so instead of grounding with the preamp you go directly to chassis. Then again, this whole paragraph was pure conjecture. Bottom line is, I have performed the preventative repairs I am recommending. No problems here. YMMV.