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Relic from the junk box

Many years ago I built a SWL SW40. I didn’t us it much as I then built a DSW40. As much as I liked the new features I just didn’t like the DDS tuning so sold that one on.
The SW40 remained in the junk box through house move after house move slowly getting battered and bruised with no case to protect it.
So I recently pulled it out the junk box and re cased it, powered it up and found a few issues as you would guessed. Tx was ok ish but didn’t like the slightest miss match on the antenna. Frequency was on still so that was good but rx sensitivity was way down but I could hear stations so it was working. Poking about I found the tunning coil looked damaged and turning the core made no difference to peak up the rx.
I had a spare so I removed to old one that just fell apart and immediately the old girl sprang into life peaking the rx well. I then re aligned the tx and found it was set to the max out put possible and just needed pulling back to about 1.5w to stabilise it.
I do like the old analog tuning and the tone of the rx and s nice to listen too. The side tone is also just right. Not sure why I didn’t use it more and will be putting it back into service. Only down side is its tunning range 7.025 to 7.055.

6 Likes

I love the sound of the RX on the SW series, very nice to listen to. The sidetone is pleasant too. I have an SW-20+ which I built myself, I put it into a homebrew PCB stock case, which I painted to mimic the original SWL case.

Later I added a keyer speed control knob as the N0XAS Picokeyer menu is a bit tedious.

I acquired a built SW-40 in return for doing a soldering job for someone, the PCB seemed OK but the home made case was shocking, so I added a Picokeyer and frequency counter and rehoused it a box from Maplin(remember Maplin?), in trail friendly format.

By the way the SW+ series is still available, being offered as a full kit By Midway Eletronics.

http://www.midwayelectronics.us/qrp/

73, Colin

I had seen the Midway kits. Love the simplicity of them. Little fiddle with and just does what it was intended to do.
Now do I take it down to Dartmoor or the QCX I just finished.
SW40 is 40m as the name suggests and the QCX is 30m.

I also built the QCX for 30m, for some reason I’ve never gelled with it. Yes, the software is fancy etc, but I’m not a fan. Getting a decent power output is also hard work.

I built a 1W40 from W8DIZ last year and coupled it to a 5 watt amp, also from W8DIZ. Diz has now made a kit splicing the 1 watt transceiver and 5 watt amp into one unit- might make a good SOTA rig.
http://www.kitsandparts.com/5watters.php

Currently on my bench is a 1W30, I bought the kit last year but I’ve only just got a work bench up and running at my new QTH.

Good luck with your projects!

Thats an interesting kit. Interesting to see how it works out. I had trouble with the QCX and power. Got 3w at 13v and left it at that.
The sw40 is much more robust to be out doors but the QCX is very clever.