KPA100 Initial Test

	I wound most of the toroids and went back to stuffing parts into the KPA100 board. It turned out there wasn't much left to stuff to arrive at Initial Test; it was mostly a matter if installing all the ICs and a few of the back-panel connectors. Here's the test setup, including the modified ribbon cable (and accompanying modified plugs on the K2 controller board and the KPA100 board).
	And here's start-up status message ... that was a good feeling! And all voltage tests for Initial Test were well within spec.

Lots of KPA100 Capacitors

Having finally gotten through the large number of capacitors to be stuffed on page 17, I thought it was time for a posting with some pictures.

Man, there are a lot of capacitors in this project! Most of it was pretty straightforward, with some exceptions. C26 (a 33pf disc ceramic) lead spacing was wider than the spacing on the board and it was difficult getting the leads bent (and I was worried about breaking them, post-RFC9). Also, a little worried about space for all the inductors amid the forest of 1KV capacitors in the filter area.

There's quite a bit of detailed instructions on p. 15 about stuffing the .01 uf .1" lead spacing capacitors on the bottom of the board. The recommendation was to "remove any U-shaped bends" to ensure that the top of the capacitors are less than 3/16" off the board. Well, I think the bends are necessary to get the hole spacing right, so I left them alone. The caps are small enough so that they fit within 3/16"; see the photo.

The other instruction for the bottom-mounted capacitors concerned minimizing the amount solder used on the top of the board for these caps. This was necessary because the top-mounted relays all sit directly on top of the solder pads and have a very small, but consistent, clearance above the board. This was easy to do, and there were no problems later on with stuffing the relays.

Finally, I was unable to get RFC9 locally. I wrote to Elecraft's part line this past Monday, and had the replacement RFC in hand in Thursday morning's mail(!). Another great job by Elecraft staff and, for a change, by the USPS.

Taking a break from part-stuffing and am winding inductors, so they will be ready to stuff when I get there in the instructions.

RFC9

I stuffed most of the resistors and was getting a start on the RFCs. I fiddled with the leads for RFC9, trying to get it to sit flush against the board, long enough to succeed in breaking off one of the leads. It was then that I had a look at the e-mail reflector, did a search on "KPA100 RFC9", and immediately got a hit. Someone was wondering about the same thing and was referred to this document. Well, I wish a reference to this document was included in the KPA100 instructions. It seems that a number of years ago Elecraft stopped using sub-miniature RFCs in favor of miniature RFCs; however, the hole spacing on the KPA100 board fit the sub-miniature parts.

The document illustrated how best to form the RFC's leads, which I was able to do for the rest of the sub-miniature parts with no difficulty. You can see it best in RFC7. Well, on Monday, I'll go over to You-Do-It and see if I can find a replacement for RFC9; otherwise, I'll need to write to Elecraft.

One other construction note: I stuffed D1 to D8 on the bottom of the board, but the instructions did not say whether these are to be soldered on the bottom or top of the board. I looked back at the few bottom-mounted parts I had previously stuffed and, in each case, the instructions were explicit about soldering on the top. Since nothing was said here, I decided to assume that this meant "solder on the bottom", which I did.

Getting The KPA100 Underway

My plan was to start work on the KPA100 (Elecraft's 100 watt power amplifier enhancement for the K2) in December and the kit arrived via UPS this past Tuesday. I had kept all the little envelopes and ziplock bags from the K2 kit and decided to sort out all the KPA100 parts while doing the inventory. You can see the result in today's picture.

There aren't many resistors in this kit, but there are loads of capacitors. They are sorted out in the middle tray in the back, with the small lots in the envelopes to the right. As you can see in the right foreground, there will be quite a few inductors to be wound. All the relays, hardware (nuts, screws, washers, etc.), wire, speaker, fan, and so forth, are sorted out into ziplock bags and are back in the box, awaiting their turn.

W1 Completed and On-line

Here's the completed W1, on-line and in use for the CQWW CW contest the last weekend in November. The meter worked fine right "out of the box" and I used it throughout the contest for tuning the end-fed wire I use on 40 and 80 meters.

There were no glitches during construction. The only really time-consuming part of the project was winding T1, which I did while waiting for the missing caps to show up in the mail. I also put together a serial cable to try out the software that can be downloaded from the Elecraft web site. At first it seemed like the software didn't work. However, testing using HyperTerm on my PC revealed that the serial cable was picking up RF from the K2; winding the cable several times through a large toroid solved the problem, and the software worked great.

By the way, running 10 watts into dipoles and my 80/40 meter end-fed random antenna resulted in 165 contacts in the CQWW contest, including contacts in Australia and Japan on 20 meters (and thanks to both ops for hanging in there with me to get my call sign correctly)! Still can't decide whether I need additional filters; I'll see how the contest goes next February, I guess.

Elecraft W1 Wattmeter/SWR Bridge

My Elecraft W1 kit arrived in the mail yesterday. It weighed 1 pound and was therefore too heavy to be shipped USPS First Class. However, another shipping option was USPS Priority Mail, which arrived here as fast as First Class and was way cheaper than UPS.

I inventoried the kit upon arrival and it was unfortunately missing all 8 .01 uF capacitors. I wrote to Elecraft's parts e-mail, got an immediate response, and just received an automated e-mail telling me that the parts were just shipped USPS First Class ... should be here Thursday.

Here's the W1 kit (minus the missing capacitors) sorted and ready for construction. Immediately after I took this picture, I fired up the soldering iron and stuffed most the resistors and the two resistor packs.

N-gen

I ordered the N-gen kit last Thursday and it arrived in USPS mail today. It was a very simple kit, with very few parts. I guess I still don't understand Elecraft's pricing on this (a tiny fraction of the parts in the K2 at about 8% of the cost), but it was fun to put together and will be a nice tool in my shack.

	Here's the N-gen, ready for running through the filter alignment procedure.
	Here's a hi-res closeup of the completed N-gen. The MAR-1 was the only component that I had to puzzle over, but finally decided to install it using the SMT technique I used when I built my PSK-20 last year, i.e., I put some solder on each pad first, placed the part, then soldered down one lead, then gronched down and soldered the rest.

The next step will be to align all the filters using Spectrogram and the very detailed procedure described in this document at the late N0SS's archived web site.