fieldflower Messages: 71 Registered: July 2004 Location: Sweden
Member
Hi,
I'm trying to get stuff together to complete my "new" 300 PA.
The stuff I'm missing:
- A jack (the "To monitor module" one).
If You could tell me a replacement jack that's similar enough that'd be great.
- Washers and nuts for some of the front panel jacks (both washers).
Just dimensions would be good, so I buy the right ones (and don't break the jack threads...)
- A couple of the rubber thingy screws/nuts for the reverb tank.
Is there some kind of replacement for this?
The jack I would think you could get from any electronics' supply company......it looks to be a standard RCA input jack; the rubber bushing for the tank, doubt those are available anywhere but you can use anything made of rubber since all they do is cushion the tank from vibration. You might look in the plumbing department for faucet washers.....they should work. The washers and nuts for your input jacks....never seen those sold separately so you will probably have to just order new jacks and use the washer and nuts from them....they are all universal.
Of course if you have more money then sense, there are lots of these amp listed on ebay right now and you could buy it for the parts.....lol. Just kidding. Hope this helps.
pleat Messages: 1452 Registered: June 2004 Location: Belding, Mi
Senior Member
The K300 PA didn't use RCA jacks. Any standard 1/4" jack should be an easy find, at least here in the states. Not sure about Sweden. The reverb tanks in the slant metal face amps, (K150, K250, K300 and K600) are mounted on the back wall of the chassis. Kustom used a rubber sleeve with a bolt molded on each end of the rubber sleeve. Acorn Nut on the chassis mount side and a lock nut on the reverb tank side.
I've never looked for a replacement reverb tank stand off bolt. You may have to find a donor amp for those mounting bolts.
pleat
My apologies....I was looking at my K-200 head. Late night last night. Pleat of course is right about the tank.....I've never seen those bolts as well. Maybe that extra amp wasn't such a bad idea after all. I'll open my 300 this weekend. I'll bet I can come up with something that should work.
fieldflower Messages: 71 Registered: July 2004 Location: Sweden
Member
Yes, finding a new jack for the Monitor out should be fairly easy (if the cut cable can still reach the jack... ).
And it doesn't matter enormously to me that it looks stock on the inside, so any metal mono jack will do...
Tried a couple of stores for washers, nuts and some kind of rubber mount thingy but came up empty.
Washers they had but not the right thickness, so I'll keep looking for those at the same time as the jack nuts.
The loose jacks will have to hang on the inside a while longer I guess. It should be pretty standard instrument jack nut size (although there are a few different), so I'll keep looking.
Didn't even find a nut for the rubber mounting (I have 3 rubber thingys but only 2 nuts).
I resorted to steel wire, just so I can try the thing out sitting on 3 mounts.
Finding a donor amp is a little challenging in Sweden...
I've only seen 6 TnR Kustoms overall in ads, IRL, etc, and I own 3 of them. (The other 3 were two 250's and one Hustler).
And even if I found one I'd quickly adopt it and promise it that everything would be ok...
stevem Messages: 4736 Registered: June 2004 Location: NY
Senior Member
I have had to make the vibration stand offs to mount the reverb tank.
Get some black silicone sealer and some machine screws and nuts, here in the states I use 6/32 size stuff.
Place a oversize blob on a Ciramic plate and set you two screws in the stuff.
Support the screw ends with something to get them level and in plane with each other and then let the silicone fully set up, when it has cut if off the plate with a single edge blade and then further trim it up to get it kinda square in shape like the stock factory one was.
This is about the best your going to do for a replacement other then making a plastic box form and using a latex casting compound which cost 8 times more than a tube of automotive silicone, but also the Laytex will not hold the screws as well!
fieldflower Messages: 71 Registered: July 2004 Location: Sweden
Member
Yes, that was smart! That I will do.
Thinking it should be possible to make very close variants if setting some kind of washer on the bottom screw, making a tube of electrical tape the same size as the washer, putting in the silicone sealer, and then seating the second screw head (with washer on) on top of it all. Should make pretty much the same rubber cylinder with crews as the original.
OK, have tried it out now. It's not in perfect condition...
It's making some kind of hissing/cracking sound that I cannot make out coming from any pot or jack. A little forest fire sound.
There's also some kind of frequency dependent distorsion that's there pretty much all the time when playing a little louder than bedroom volume.
The reverb is not working at all regardless of channel or master settings. Absolutely no change in sound when turning those controls.
When looking into the reverb tank everything is looking fine except that there is a small spot of something brown on one of the red (whatever the component is) that sits at each end of the reverb tank.
Could it be something burned up? That could create the non-existent reverb sound?
Other than that it's nice. Power-on and power-off is nice and smooth on this one.
Changed the fuses on my other PA, and power-on is smooth, but power-off is like a pistol shot.
I guess both of these will be visiting my dad...
Really good to have 2 of them with different errors - should make troubleshooting easier to have something to compare with.
Any ideas for what might be wrong is deeply appreciated.
Just thinking now - the jacks hanging free on the inside - could they cause the something-is-not-soldered sound? Volume was at zero on them...
Check the connections on the reverb tank where the RCA jack plugs into the tank. Make sure they are making contact with the pin. That was the problem with one of my tanks. Some of my amps pop when you shut them down as well.
fieldflower Messages: 71 Registered: July 2004 Location: Sweden
Member
Iowa Boy wrote on Sat, 30 May 2015 19:58
Check the connections on the reverb tank where the RCA jack plugs into the tank. Make sure they are making contact with the pin. That was the problem with one of my tanks. Some of my amps pop when you shut them down as well.
I cleaned them up real well, but I didn't check that there was actual contact. Will do that.
Do Yours also pop in the "oops, there went the speaker" level?
Doesn't do it anymore since I play the amp more often now. Not sure if the capacitors have gotten re-conditioned and that was the problem in the past. Someone hear surely knows what it causing it.
Do you have an ohm meter? If you do, use it to read the resistance across the input and the output jacks of the reverb tank. You should read approximately 150-200 ohms.
If you get this resistance reading, then the tank coils are okay. If either side is off, then you have a problem with the tank coils or the internal wiring, etc.
pleat Messages: 1452 Registered: June 2004 Location: Belding, Mi
Senior Member
Isn't the reverb tanks on the slant metal face amps 25 ohms at one end and 180-200 on the other side? I'd compare both reverb tanks of your K300 PA heads. No telling if the reverb tank in question, is even original after all these years.
stevem Messages: 4736 Registered: June 2004 Location: NY
Senior Member
Bill may be right I can not say as my 300 has no tank and its reverb circuit is not like the non pa metal face amps as its driven by transistors and not a 5558 chip, and on the out bound side it's the oposite also with a IC chip instead of a transistor!