The JT30 page has been rewritten (again). I've done this a dozen times since the first version appeared on AOL Pages about 25 years ago. I reorganized everything so it makes more sense, but I expect there are going to be a lot of linked pages that can't find the moved page. I'll be trying to fix these over the next month or so.
The next step is to finish the work I started on the store. I have lots of things that I'd like to sell including elements, cords, mics and amps.
I have been digging in the "bat cave" in the back of my cellar.
I found this Kalamazoo 2 amp. It is missing the knobs and the back panel. It did not work.
I figured that it needed a cap job, which is easy on a Kalamazoo so I did a nice sloppy job and replaced the firecracker caps with three Atoms.
I am not an amp tech and don't play one on TV. I know the vocabulary, plus I can read a schematic.
The amp was totally quiet. I pulled out my VOM and checked the voltages and compa...red them to a schematic that I found online. The voltages were a little high, but not too far out of wack.
I then went through the schematic, starting with the inputs and checked the values of the resistors. There was a new resistor so I suspected that it had been serviced once and had worked at some time. All of the resistors that I checked were good until I came to a 100k resistor in the second stage pre-amp and it just wasn't there. I am assuming that someone robbed the amp to fix something else at some point, but they did it without leaving a clue that it was done.
I checked and rechecked, but there wasn't even a place where the solder was disturbed. I noticed also that a little 15pf cap was in the wrong place. I moved the cap. Luckily I had a 100k ohm resistor in my stash and put it where it belonged.
The amp works!!! Nice warm Kalamazoo tone. Louder than I remember than the last Kalamazoo that I had.
I am going to cut a back cover so the high voltage is covered and see if I have three knobs that look alike. Then it is going out on eBay. These things go for around $200.
I don't know where it came from or when I bought it, but there was a penciled tube layout written on the back of pay stub. David Buckley worked at Millrock, Inc. during the summer of 1994 and wrote out the tube layout. There is a Millrock in Sanford, ME, and another one in Virginia. I must have picked up the amp when I went to Maine with Larry back in the 1990s.
Another item for eBay.
This is a tube amp that hums. All of the old amps need a cap job, but this one needs a 60, 40 and 20uf set that would cost more than the amp is worth to me.
It is 20 inches high by 16 wide and 8 deep. It has an 8 inch speaker and the amp includes a tremolo which dates it to the 1950s....
The transformerless tube lineup is HL92/50 (50C5), 35W4, 12AV6 and 12AU6.
It is light weight so the shipping is going to be under $20, probably.
I put this out on eBay today. It is a Brumberger three tube intercom. It could be used to make a small Cigar Box amplifier, but it requires about $20 worth of electrolytic caps to fix and I'd still have a low power amp that is neat, but not that useful.
It started on eBay at $10 which is the what the tubes would go for if I listed them separately.
$25 at the West Hartford Guitar Show. This is a "transformerless" design amp with 2-50L6 power tubes and 2-12SC7 preamp tubes and solid state rectifier.
I am guessing its an old Valco amp.
It "Motorboats" when I turn it on which usually means a bad electrolytic cap in my experience, although could be a symptom of several different things. It has a vibrato circuit so it could be that.
I will change the smaller 25uf cap first. This is what has worked before. It has two "can" ca...ps so I try the big one first.
If I can stop the motorboat sound I'll change the power cord to three wire.
50L6 tubes are rated lower power than 6L6 tubes and it has a 10 inch speaker so I assume it is about the same power as a deluxe.
Cosmetically it could use a bath and some glue to hold the tolex down. This might be my February project.
It's not like I have too few amps. I've been selling crap on eBay. I think I will be dumping all my crappy garage sale solid state amps and a few no-name amp cabinets that I bought about 10 years ago when I thought I might build some more amps. If you live near West Nyack, NY and need a crappy solid state amp let me know via messenger.
Sometime in the late 1990s I recorded a few MP3 files for my website. I have never been a good player, but when I recorded these I was pretty clean. I stopped playing for a few decades and recently started up again, and I wish I could play as well as I did back then.
For your entertainment, this a beginner's "how to bend" track.
Woke up this morning...
Refurbished an MC-101 element.
Decided to do something that I've been thinking about for a while....
I have some piezoelectric acoustic guitar pickups. These are the kind that you glue to the inside of an acoustic guitar in order to get a nice sound. They are sensitive and many acoustic players use them. They are popular with cigar box uke builders because they get a good sound and are cheap. I think that I paid $2 for 6 so I could experiment with them.
I found that the pickups need to be attached to something that vibrates and they don't do much of anything without a sounding board. I tried heavy plastic from a food container and some heavy duty aluminum foil, but they "buzzed".
The secret is the bottom dome from a Coors Light can. I live near a high school so I can pick up a few dozen of these from the road in front of my house every weekend.
The dome itself is about two inches so it cuts down perfectly for fitting into the element. From the picture you can see that I epoxied the pickup on the inside of the dome. The dome is stiff enough and large enough to vibrate without buzzing. It is thin enough that it picks up the vibrations from the air without muting the sound.
I pried the metal perforated screen from the element, cleaned out the crumbled crystal and soldered the leads from the pickup to the contacts on the element. I epoxied the dome in place and snapped the screen back in place.
The element gets part of its tone from the pickup, but the heavy pot metal back of the element also deadens stray sounds and gives the element its character.
I am very pleased with the refurbished element. I sounds very much like a new MC-151. It is hotter and more responsive and has more frequency response, but it overdrives like a real element and does sound nice.
I can't find the original bunch of pickups that I bought. I have a very messy work space, but I bought 6 more from China for 99 cents.
I have a box of dead elements. I will collect some more beer cans and refurbish the bunch. I'll put them in tail light elements and see if I can sell them on eBay cheap. Every time it snows and I can't go out I'll make a couple.
I went down to The Turning Point Cafe last night to see the Nick Moss band with Dennis Gruenling and Steve Guyger. Larry got their early and reserved a space in the front row.
It was a good night Dennis and Steve great harp players. It was Nick's birthday so we all got champagne.
Here are some pics.
A few weeks ago I was talking about the sheet metal mic that was rusted out. The grill looks very much like a T-3 grill so I decided to repair the shell with J-B Weld. The weather is windy and cold outside so I finally got a few hours to work on it.
I used a piece of metal screening to use as a base and built up the shell near where it should be.with the epoxy.
I used a discarded stanchion from a tail-light mic project and drilled out the hole for a long thread panel jack. Th...e stanchion adds lots of strength to the project. The epoxy, although strong, may not stand up to gigging with a 2501 or a jack installed. The stanchion will add the strength the mic needs and distribute the forces out from the hole so more of the shell absorbs the tugs and pulls.
Here is a picture before I add some more epoxy around the edge of the stanchion. This week I will grind off the excess J-B Weld and sand it. I will go to Home Depot and pick a nice paint color.
I am trying to decide if I should put an expensive element in the mic or use a refurb or CB element.
I used to go up the Elephant's Trunk flea market in Connecticut every weekend. I pulled a bunch of mics from there, including a T-3 in the bottom of a box of plumbing supplies for $3.
I got this mic there pretty cheap as I remember, but it really is in bad shape and not worth much.
It is made of pressed sheet metal. It has a cool grill. The body is not strong enough for the cable and stand connectors and it rusted out and broke.
I am going to get some Bondo and try... to build up the base. I'll sand it smooth and put in the connector and volume control. I think that if I use some metal screening as the matrix for the bondo it might stand up to use.
When I get around to finishing it, I will post here.
A long time ago I traded a few elements to a guy who made gaskets. He sent me this resin casting of a green gullet grill. I found it while reorganizing my mess in the bat cave. I have to think of what to do with it.