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I spoke with Phil at Heyboer this morning. Phil is a very nice guy and gave us the price break we wanted. I told him we had four orders, and he gave the price as though we had five. The final specs are: - 100 mA capacity from the HV (400-325-250-0-250-325-400 mulit-tap) - 3A each of 5V and 6.3V, one 5V and one 6.3V - both of the heater windigs CT The cost is $66.30. The bill will be sent with the order and is payable in 30 days. The ship time is two weeks. When you call Phil (616)842-5830) to place your order, reference HTS-8074 or my name, Colin Hester. I did not ask how this will be potted, so if anyone has a preference I'll go along with what ever. Let's make it easy on Phil and all be on the same page. I did place my order today. Please sound off when you've ordered......Colin
O'kay for me. Except I forgot to order the choke. Anyone using them for your choke piece? I did not ask if it was potted because Phil wasn't there, just placed the order with his receptionist.
Tryed to call but got there mechine. So I sent an e-mail with ref # that should work...John
I just sent an E-Mail to Heyboer to order one of their HTS-8074 transformers.
Hey-Hey!!!, Colin, you ref'd potting. I think you guys are getting an unpotted version, $66 is too close to the premium paid for potting. Vertical endbells, like ST.70 outputs, or either of the Dynaco Mk.III's irons. Spent the evening wrestling with layout on a 18w x 13.5 deep top plate. The box is 5" thick and in some places I am running short of room. Three L-C filters, two for the filaments, and the main HV give this thing a mass like a respectable power amp. I am losing a half inch at each edge, so the realestate is a bit smaller. If you guys go for the top plate and wood base construction, getting a haldle on it to pick it up is sometimes a PIA. Take a 1" holesaw and at the lower edge make four overlapping holes so you can stick your fingers in. Make the edges a bit rounded, and it is a great sol'n to the trouble of sticking handles somewhere. regards, Douglas
Damn, I just cut a 12 x 12" copper plate for the top, and I thought that was being generous. Caps will be mounted such that they poke out the top. So, something like 12 x 18" would be better?.....Colin
12x12 ought to be plenty. Remember, I have twice as many things, and most of them are bigger. The amplifier section is made up of 6 valves, 2x 12B4A and 4x 12BY7A for the active loads. The first one of these I built on 5 3/4 x 11. I am going to resurrect it with 12B4's and the rest of the Guinevere circuit. I was goig to use 6 1/4" but the milling machine vise only could take a 6", so I trimmed it so I could clamp in in the vise. regards, Douglas
I've seen some amps with wood bases that look good, but some just look, well, cheap. What about having a metal chassis made? Gotta have transformer covers made too. It shouldn't be hard at all for a machine shop to do, just cut a "+" shape out of sheet metal, fold it and have it powder coated, painted or chromed. It makes all the difference in the world to aesthetics, if you asked me.
Hey-Hey!!!, There is a place in PA which does deep drawing. that method leaves nice 3-D rounded corners. I will find a link to them and post it as a reply here. regards, Douglas
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You can send the sack of money to my house, Brinks ought to be acceptable for such a sum. If not, I know some large men who are in the habit of traveling well-armed. In case you're *NOT* kidding, I'm Pentode at netscape dot com regards, Douglas
Colin, where do you get such fine swag? now we're going to watch me fumble through making a headphone amp...thanks Douglas
Haha, nice, congratulation...but 32 Ohms impedance?! OPT ... PP in your case? 5687?
Hey-Hey!!!, first is to decide on something way over the top...then to make it mine...PP of course. Small 10k:70V line out perhaps. Don't need much power. I am going to look at this when the latest revisio of the linestage is up and running. But it might be the perfect excuse to do a SE project. 2A3 perhaps? regards, Douglas
I am not even going to think of SE projects. Look what discussing it in public gets me? got a call from my wife. Muffler hangers on her Benz fell apart. droped the entire back part of the exhaust on the ground. Fortunately, it happened at the Mechanical Engineering end of campus and some Engineers, armed with a coat hanger and diagonal cutters put her back down the road. What do yo think would happen if I actually built some SE amplifier circuit? probably hole in the sub-pan and drain out all the oil. No thanks....I'm staying PP regards, Douglas
Hey, SE is not that scarry, isn`t it? What`s you think of something in your style - SE 300B with higher Ra=5k, or maybe CCS loaded "parafeed", toroidal OPT? Or "enhanced SRPP" style, 300B lower tube, triode connected EL34/6550/KT88 upper, with DN2540 CCS in the place of upper Rk? Driver - PP, haha? Or, just do "right" PP 300B, Raa=6...10k, better higher. With "monster" 300B versions and OP, say 400-450V/100mA sounds promising... But, about 2 x 60Vrms from the (simple!) driver is not that trivial to do it right, or maybe you got some idea?
Yeah! I get goosebumps just thinking about it. You don't want a German car anyway.