Most of our correspondents did not like the idea of me trying to convert my Heath HW-101 into a BITX-101. But, thinking that I still might to this, I decided to take the old rig off the shelf and see what it looked like. I liked the looks of it -- lots of space, simple circuitry, nice belts and gears for turning the many variable capacitors, no black box ICs. I could see traces of my earlier repair adventures -- electrolytic caps that had been replaced, the plastic dial clutch that I'd "fabricated" myself. Then I decided to try to fire it up. Hey, the receiver sounded very good. Next thing you know, I was getting the transmitter going. Then I was working DX on 20. By the end of the afternoon, I knew there was no way I would be tearing this old rig apart. There is simply too much soul in this old machine.
OK, so I've been wanting to build a BITX-20 for a long time. Then Steve "Snort Rosin" Smith sent me a nice 9 MHz filter, and I started to think about using it to build a BITX 75/20. But I don't really like 75 meters too much... And I have this Heathkit HW-101. I like it very much, but these rigs do not age well: Too much heat, too many cheap components, tubes on PC boards... yuck. I got tired of fixing it. I've occasionally fantasized about scrapping most of the HW-101 circuitry and turning this rig into a 100 watt linear amplifier. But I didn't have the heart to do this. Then, on the way to work yesterday it hit me: Why not take the beautiful bi-directional circuitry of Farhan's BITX design and use that to solid state most of the HW-101? Obviously I'd retain the finals and maybe the driver, and the CW and SSB filters. The VFO could be transistorized. Maybe I'd retain the tube AF amp. I'd like to add 17 meter capability. Pete Juliano took an HW-101 and added a digital dial (that's his rig in the picture).
What do you guys think? Am I nuts? Or would this be a worthwhile project?
I like it! Here we find some cutting edge radio technology that does not involve millions of microscopic transistors and thousands of lines of code. And it can be explained in a few paragraphs without resort to exotic math. It even makes use of our beloved LC resonant circuit. Quick, where did I put Billy's green laser? And where can I get some silicon nitride? http://m.technologyreview.com/view/517336/physicists-detect-radio-waves-with-light/
Well, you know that you are really in the high power big leagues when your transmitter requires a cooling pond, and you have to put on welding goggles before you examine your tubes! I especially liked the bit about how they built the transmitter BUILDING from the packing materials used to ship the transmitter (my operating desk is made from a box used to ship my HT-37!).
This is all really amazing. They built this thing less than ten years after the initial launch of commercial broadcast radio in the U.S.
Thanks a lot to Randy for doing this video and to the guys who gave the really excellent tour.
My apologies to the QRP purists who I know will have been deeply disturbed by this presentation.
QST gave the book a very nice review in their August edition. But they got the price of the paper edition wrong -- it is definitely not $45! The normal price is $20, but with the coupon code SOCIUS you can get it for $16 through 19 July. http://www.lulu.com/spotlight/soldersmoke
In response to popular demand, "SolderSmoke -- Global Adventures in Wireless Electronics" is now available as an e-book for Amazon's Kindle.
Here's the site:
For the print version:
For shipping from a printer in the U.S. (probably better for N. American buyers) Click here: SolderSmoke USA Version
For shipping from a printer in the UK, Spain, or the USA (probably better for UK and other European buyers)
Click here: SolderSmoke EU Version
The two versions are identical, except for a minor difference in the paper used. That's why the prices are a bit different.
Bill's OTHER Book (Warning: Not About Radio)
Click on the image to learn more
W4HBK's QRSS Grabber: The Amazing Pensacola Snapper (Live!)