And what did we buy today?

Anatech,

Thanks again. On thinking over the method you described, I reckon I could drill holes through the transparency with one side taped to the board, flat off the drill holes, then apply the bottom transparency, expose, develop, etch.

I've done this with alignment holes at each corner, but I had a number of failed or poor results, perhaps drilling all the holes will ensure better alignment.

I generally use laserstar transparency, and due to opacity I overlay 2 copies, which of course makes alignment all the more fiddly. However, lately I've taken to using a single sheet, and beefing up the lines with a permanent 1mm OHP pen, or even a pencil.
 
Indeed! That's a good looking board there, George.

Thanks. It does look good in the small photo, but it does contain many flaws. I live with them since these are just protos. In this case I laid this thing out over three days while my wife was in the hospital. Most of it was done on a crappy laptop and I didn't do such a great job. I started putting parts in it yesterday and have decided that I need to do it all over, since too many parts don't fit or collide. I will populate several subsections to test them. If the results are good I may build up one or both complete channels to see how it sounds. As with any of the boards that could become a Tubelab product, there will be several proto boards made before I shell out big bucks for production quality boards.

Do you guys ever have problems with failure of soldered thru-pins etc. on homemade boards with no plated vias?......I've always wondered if this was a common problem in this situation

I solder the parts on both sides, and where this isn't possible (radial electrolytics) I solder a wire to the track on the top side and run it through the hole with the part lead, then solder both on the bottom side. I have been making boards this way for nearly 50 years, and some of my old ones are still working. The boards from those days that are not still working, were not bad due to the PC board......just crappy designs, most just didn't work in the first place. They are now in the "box of broken dreams" to be robbed of parts.

I can never get the double sided ones to work out aligned properly.
In the days when cameras used film, I had my own darkroom. I used it for making PC boards too. For double sided boards I made a frame (two corners) out of old PC board material of the same thickness as the target board. Make the negative or transparency much bigger than the target board. I used 8 X 10 or 11 X 14 inch Kodalith film. Tape the frame to the negative such that the target board fits into a corner of the frame with the image in the correct place. Then tape a piece of scrap board to the negative to hold the target board in place laterally. Then tape the second side negative to the frame such that the target board is held inside this sandwich and can not move around. I usually stuck this sandwich in between two glass sheets which were taped together so that I could flip it over to expose each side. This usually worked well enough to get near perfect registration from side to side.

Now I use the toner transfer process and do one side of the board at a time. transfer the image from the print to the board on one side. Tape the other side with wide masking tape and rub it down good with an old spoon or the butt of a screwdriver handle. Etch, remove the tape, strip off the toner. Then tape over the side you just did and transfer, etch, remove the tape and srtip the second side. If the board has mounting holes you can drill a tiny hole in the center of them and use them for aligning the second side.

I use a piece of PC board material that is slightly larger than the actual board being made. Then I draw the outline of this larger board into the PCB artwork program with the target image centered in it. I then lay that on an old towel face up, place the target board onto this image such that it is exactly on ther lines that you drew in the layout program, and apply the iron to the top of the bare board. It will take a bit longer to transfer the image this way (about 5 minutes). This way you can drop the boad right back onto the rectangle, in the same place to do the second side. All errors now are caused by my $79 laser printer's less than perfect paper feed path, which got worse when I popped a $12 toner cartridge from Amazon into it, but that's how I made the board in the photo.....and the last dozen or so I have done.
 
Thanks for your replies. I guess it's safe to assume this was just some sort of glitch in Baldwin's process. They used little square pins (like wire-wrap only shorter), pressed in place at the vias. When I think about it, they were likely wave-soldering the bottom side of the boards, but the pins on the top sides would've required hand soldering. There must've been some incompatibility between the 2 processes, because it resulted in many failed joints. Kind of a shame, because it's rendered useless a lot of otherwise-viable instruments due to prohibitive repair cost.
 
Two side pcb

Here is one of my last double side home made pcb.
Always i use small guide drill for two side transperance alignment.
No vias, just two side soldering.;)
I manage to lift electrolytics a little to be possible the two side soldering.
Never failed!
 

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No, as many times as I have hunted Buffalo mountain, I wasn't aware there was an ATV on buffalo mountain (It is only two miles from me).

I have ridden 23 to Asheville, and will ride 421 "The Snake" next weekend.

I don't do much off road.

It’s a fairly easy trail for a big bike.......there’s one rocky table top that’s a little tricky but if you carry the mo it’s no problem. Brown mtn ohv down in Morgantown has a nice set of two track trail to practice on.

Don’t wanna scratch the new beastie? :D

Edit: sorry gimp I thought you had the r version......I just went back and saw it wasn’t, still could probably do the main loop at brown mtn though.
 
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I bought this

I bought this, it just kinda looked cool. I don’t have a license and I have no idea how to use it but it’s old and interesting and should be here in a few days. I believe the receiver is solid-state and the transmitter is hollow state
 

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It was hot so I stopped at Mast general store and bought a Tilley hat.
Boy, that takes me back. My wife purchased some clothing for me at that very store in 2007 after I took an unintended dunking at Lake Lure. How time flies!

I believe the receiver is solid-state and the transmitter is hollow state
Nice rig! The transmitter has two 6146As in push-pull, driven by a 12BY7 (I think). The outputs are easy to find, but the driver is becoming a bit scarce. Anyway, you should consider contacting your local ham club and see into getting a license. You'll have a blast. :)

Oh and lest I forget: a spool of waxed cord for lacing the cabling of my new amp.

73 de KT4G
 
Actually bought them last week, and they arrived in the mail Friday.

A new pair of (new re-issue) Tung-Sol 6550 tubes for my SE amp. Until now, my favorite has been the Winged ~C~, but I believe these new Tung-Sols have a bit more oomph in the bass region. The rest of the spectrum is very smooth, like the Winged ~C~.
 
Over the weekend, I bought:

1. 800 ml of homogenized Camel milk (Amul) for Rs.100 (~USD 1.40).
2. 1000 fibre washers for Rs.150 (~USD 2.10).
3. 200 anodized MS washers for Rs.70 (~USD 1).
4. 1 DFI Lanparty NF4-SLI Socket-939 mobo with Opteron 165 and 2 GB of Patriot DDR400 RAM for Rs.1.1k (~USD 15).
5. 1.5L of Black Currant Ice cream for Rs.210 (~USD 3).
6. 2x 450gm loaves of bread for Rs.70 (~USD 1).

This is India, where food is cheap and electronics are expensive.
 
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A torque cassette meter for cassette decks. I'm being pushed into servicing them so it may as well be done right. This stuff is expensive!

It's an ABEX SRT-CT-Ws. Much like the Teac torque gauge I used to have. Now I need the tape height jig and then the actual test tapes. If anyone has some of this stuff, please let me know. I should have asked here before paying for new ones.

-Chris