630m Transverter Project
I've ordered parts from Digikey for the summer workbench project, a 630m transverter. With the nice 630m WSPR signals received here from Roger (VK4YB) this spring, I think it might be possible for us to work each other using JT9, if the path continues to improve over the next few seasons. On more than one night, Roger's signal was at JT9 QSO levels and had we been on a schedule, a QSO may have happened. Roger's signal was peaking late in his evening, which for me will require making schedules in the wee hours of the morning.I've been wanting to build another SMD project for some time since making a little SMK-1 40m transceiver several years ago. This was a very inexpensive kit put out by the NorCal QRP Club as a way of introducing SMD construction techniques to beginners. I found working with the 1206 sized parts (basically the largest ones commonly available) to be fairly laborious and would only solder a few parts at a time before setting it aside for the next day. I think my frustration had a lot to do with my positioning and soldering methods and I'm anxious to try doing it with a more refined technique. As I recall, there were 72 SMD components on the board and it took me a couple of weeks to finish it all.
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| My SMK-1 40m SMD transceiver |
The parts I have ordered are also 1206 sized but the older I get, the smaller these things seem to look. The transverter will be based partially on the popular G3XBM circuit but will eliminate the PA. Instead, I'll just use a few volts of the transverted squarewave signal and a doubler, so that I can feed the signal directly into my present homebrew amplifier which uses two switching FET modules into a power combiner. Hopefully this system will let me run several of the non-linear digital modes such as WSPR, JT9, JT65 etc.
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| My 630m PA |
As a way of getting back into the SMD-soldering groove, I have ordered and now received, an "SMD Practice Kit" from E-Bay ... a real bargain at $1.78!
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| courtesy: Tradeworld2105 |
Although there are many similar practice kits being offered on E-Bay, this was the only one I found that had two IC's to practice with ... all of the others had just one. Since the transverter's doubler circuit has an IC chip, a couple of practice opportunities will be helpful. My only hope is that I don't run out of SMD steam with the practice board before getting down to the actual transverter board.
As soon as the parts arrive from Digikey, I'll start designing the transverter's PCB ... but with all of the usual distractions of summer, as well as trying to maintain vigilance on the magic band once again, my summer project may not progress as quickly as I hope.
All of this assumes that my old eyeballs hold out as well.
Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].
Weekly Propagation Summary – 2016 May 23 16:10 UTC
Here is this week’s space weather and geophysical report, issued 2016 May 23 0405 UTC.
Highlights of Solar and Geomagnetic Activity 16 – 22 May 2016
Solar activity was low with only B-class and C-class flare activity observed. Regions 2544 (N20, L=295, class/area=Dai/160 on 16 May) and 2546 (S07, L=223, class/area=Cho/550 on 21 May) produced three low-level C-class flares between them, with the largest being a C1.8 at 16/1525 UTC from Region 2544. No Earth-directed coronal mass ejections (CME) were observed during the reporting period.
No proton events were observed at geosynchronous orbit. However, there was a slight enhancement on 16 May from a long duration C3 flare that occured previous to the reporting period. The greater than 10 MeV proton flux reached a maximum of 1 pfu at 16/0030 UTC.
The greater than 2 MeV electron flux at geosynchronous orbit reached high levels on 16, 17, and 19 May and moderate levels on 18, 20-22 May.
Geomagnetic field activity was mostly at quiet to unsettled levels from 16-20 May with an isolated period of active conditions on 17 May in response to a positive polarity coronal hole high speed stream (CH HSS). G1 (Minor) geomagnetic storm levels were observed during the 0600-0900 UTC synoptic period on 21 May due to influences from another positive polarity CH HSS.
Forecast of Solar and Geomagnetic Activity 23 May – 18 June 2016
Solar activity is expected to be very low (B-class flares) to low (C-class flares) levels throughout the outlook period.
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach high levels on 28-29 May, 01 Jun, 03-09 Jun, 12-13 Jun, and 18 Jun. Moderate flux levels are expected for the remainder of the outlook period.
Geomagnetic field activity is expected to reach G2 (Moderate) geomagnetic storm levels on 04 Jun and G1 (Minor) geomagnetic storm levels on 05 Jun due to the influence of a negative polarity CH HSS. Active geomagnetic levels are expected on 26 May, 30-31 May, 02-03 Jun, 06 Jun, 11-13 Jun, and 17-18 Jun due to various recurrent CH HSSs.
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Live Aurora mapping is at http://aurora.sunspotwatch.com/
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Inverted L
I needed a cheap and relatively unobtrusive solution and I found one in Len Paget's (GM0ONX) design for an inverted L. The full details were printed in the Practical Wireless magazine several years ago and PDFs are available for download from Len's website. The designs make use of coaxial traps, one for the 80m version, two if you want to add a top-band (160m) option.
Opting for the smaller 80m version I set about building one. Using an old fibre-glass fishing pole about 5m high at the far end of the garden tucked behind the summer house which I could collapse down and then retract the wire elements when not in use so hiding it from view.
The fun and interesting part was building the trap. They are formed by coiling some coax, in this case RG58, round a former such as plastic waste pipe. I had a bit of scrap pipe but it was 32mm not the 40mm diameter type described in the article, thinking it couldn't make 'that much difference' I built one using the same number of turns but the resultant antenna wasn't anywhere near resonant according to the analyser.
I decided I needed to test the trap's frequency response. I found a YouTube video by Dave Tadlock (KG0ZZ) where he demonstrates using a MFJ 'Grid Dip Meter' adapter on an MFJ antenna analyser to test coaxial traps.
The adapter consists of nothing more than a coil of wire on a suitable former so I made my own to use with my AW07A analyser. It worked a treat and I discovered my trap was way off frequency. In the mean time I had located a useful PDF document by David Reynolds (G3ZPF) which informed me I actually needed 180cm of RG58 round a 32mm pipe to make a suitable 7MHz trap, so I made another.
I made a small video showing the traps and how I tested them.
The resulting antenna seems to perform well, but it does sag a little due to the weight of the trap and wire and the flimsiness of the pole. But I have made a number of contacts on it and used it during the RSGB 80m CC Datamode contest a few weeks back. It was my first go at this contest but once I got the hang of operating it was great fun.
Andrew Garratt, MØNRD, is a regular contributor to AmateurRadio.com and writes from East Midlands, England. Contact him at [email protected].
Inverted L
I needed a cheap and relatively unobtrusive solution and I found one in Len Paget's (GM0ONX) design for an inverted L. The full details were printed in the Practical Wireless magazine several years ago and PDFs are available for download from Len's website. The designs make use of coaxial traps, one for the 80m version, two if you want to add a top-band (160m) option.
Opting for the smaller 80m version I set about building one. Using an old fibre-glass fishing pole about 5m high at the far end of the garden tucked behind the summer house which I could collapse down and then retract the wire elements when not in use so hiding it from view.
The fun and interesting part was building the trap. They are formed by coiling some coax, in this case RG58, round a former such as plastic waste pipe. I had a bit of scrap pipe but it was 32mm not the 40mm diameter type described in the article, thinking it couldn't make 'that much difference' I built one using the same number of turns but the resultant antenna wasn't anywhere near resonant according to the analyser.
I decided I needed to test the trap's frequency response. I found a YouTube video by Dave Tadlock (KG0ZZ) where he demonstrates using a MFJ 'Grid Dip Meter' adapter on an MFJ antenna analyser to test coaxial traps.
The adapter consists of nothing more than a coil of wire on a suitable former so I made my own to use with my AW07A analyser. It worked a treat and I discovered my trap was way off frequency. In the mean time I had located a useful PDF document by David Reynolds (G3ZPF) which informed me I actually needed 180cm of RG58 round a 32mm pipe to make a suitable 7MHz trap, so I made another.
I made a small video showing the traps and how I tested them.
The resulting antenna seems to perform well, but it does sag a little due to the weight of the trap and wire and the flimsiness of the pole. But I have made a number of contacts on it and used it during the RSGB 80m CC Datamode contest a few weeks back. It was my first go at this contest but once I got the hang of operating it was great fun.
Andrew Garratt, MØNRD, is a regular contributor to AmateurRadio.com and writes from East Midlands, England. Contact him at [email protected].
Really cheap cheap BM-800’s!
The price proved so irresistable, I decided to purchase another pair and they arrived boxed with all the accessories within a couple of days of clicking the mouse:
Really the price is so stupid, you could fill the cupboard with a load. If you make a mistake with the mods or a slip with the soldering iron you are not going to end up red faced or feel it on your pocket. The G4IZH project is now really viable for a club, to get your heads together, purchase a shed full and have a modification night.
Link to seller:
(3/7/16) The offer has now ended, so I have removed the sellers link. Hope you got yours?
* Please note this is a UK seller and I don't know if they ship internationally? I have no connection with this company only to spread you Amateurs with the news.
Steve, G1KQH, is a regular contributor to AmateurRadio.com and writes from England. Contact him at [email protected].
Really cheap cheap BM-800’s!
The price proved so irresistable, I decided to purchase another pair and they arrived boxed with all the accessories within a couple of days of clicking the mouse:
Really the price is so stupid, you could fill the cupboard with a load. If you make a mistake with the mods or a slip with the soldering iron you are not going to end up red faced or feel it on your pocket. The G4IZH project is now really viable for a club, to get your heads together, purchase a load and have a modification night.
Link to seller here.
* Please note this is a UK seller and I don't know if they ship internationally? I have no connection with this company only to spread you Amateurs with the news.
Steve, G1KQH, is a regular contributor to AmateurRadio.com and writes from England. Contact him at [email protected].
Out on the trail with the KX3
| The bike all loaded up |
After loading up the bike the first thing I found out was the kick stand on the bike would not support the bike and the loaded side bags. It turned out to be a fine balancing act when it
| Diamond K400 mount |
Here is a list of the items I am packing:
KX3-on it's own with no Pelican case
Extra battery just in case- The Tracer battery pack
18 gauge counter poise- only for 20m at this time
Pens, paper and 3x5 cards with programming Kx3 instructions
Headphones- I don't use ear buds as my hearing is not that great and any noise around me tunes out CW.
Trunk lip mount base for antenna- Diamond K400
Miscellaneous items- antenna connectors, adjustable wrench, tire repair kit for bike, hat, sunglasses and so on.
Lets get to the trail adventure..........I was able to bike to one of my pre picked spots down at the Lake where a nice size picnic table was available. The antenna mount setup worked great on the bikes rear rack which I mounted back at the condo in case there was issues. I attached the counter poise via a male female 14 gauge connectors. The rig setup was straight forward as I have done this many times in the past. I fired up the rig and I wanted to see at this point if the counter poise was sufficient for a decent SWR and it was. BUT after
| The setup |
| The surprise error code |
Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].



















