Friday, 7 April 2017

My home-brew mini paddle for QRP rigs

Here I am again with a little bit of spare time and a love of radio. Yesterday I was dreaming up solutions for a portable paddle morse key and thinking about how much it might cost me to buy a new one. My solution was to have a go at making my own. I followed one simple rule copy the basics of something that works, my palm mini paddle uses PCB material to make the arms for its paddle and I knew I had some stuff in the junk box that would allow me to experiment before shelling out any money on a new key. The result was what you see in the picture below and on the video linked to this blog post.
I am really happy with the simplicity and ease of use for what is essentially made from scrap materials and costing me nothing more than my time and effort. I have made a few contacts on the key connected up to the FT-1000MP Mrk V and to the HB-1A you kits radio. I had no problems other than a few errors due to my lack of familiarity with a new key. My results show its always worth having a go to see what you can come up with before spending any money on something to solve the problem.

Saturday, 7 January 2017

Laserbeam delights - Audio DSP filter for CW



Last Monday I had a bit of free time and I have been planning to help Keith G0RQQ put his new audio CW filter into a box for some time. It made sense to use the bench in the workshop here because everything is set up and read to go, Keith preferred that option to destroying the dining table at his place. He has a Laserbeam dual band filter module from Sotabeams http://www.sotabeams.co.uk/dual-bandwidth-filter-modules-ssb-cw/ and I have to say it is a great bit of kit for something so small. Well worth the money to add a new level to older or wider receivers.

In the classic QRP style Keith wanted to fit the board into an Altoids tin to be the ideal companion to his Frog sounds QRP single band 40m rig. Keith did add on the additional filter integration kit from Sotabeams for an additional £5.50.

VK3YE has done a great look at this and has a video demonstrating its use on home-brew kit. Have a look at the video to get a really good idea of how this works.



We really were blown away by the performance of this little box of tricks when we tried it on the big rigs in the shack. The filter is a brick wall when switching between wide and narrow and it is excellent to listen to. I think this filter may well be on the cards for me to pick one up very soon to play with the rigs here at M0TEF towers.





Sunday, 1 January 2017

Some QRP fun, 40m QRM and the Virgin Media TIVO box

I have been enjoying my festive break from my work and spending a couple of weeks sorting out some projects and radio related experiments. I have fired up the little QRP rigs to work a handful of stations on CW. I never managed to work anything on the SW-20 rig with 2.5w into the butternut HF-9v antenna so moved onto the 40m band using the doublet antenna. It always seem more fun to me to work with the basic kit than with the big station and I seem to get a bigger kick out of working stations from the simple rigs, battery power and wire antennas.

I did work a few stations around Europe but it was at this stage I felt the need to seek out the noise on the 40m band. You can see below the SW-20 with my spare HyMound Key and world map on the bench in the shack.




I promised myself I would get to the bottom of some QRM that I was experiencing on 40m and causing issues to RX of weak signals on the 40m Band. I used my trusty little HB1B with a small telescopic antenna to check where the RFI was coming from, it turned out that the issue was from the TV set.

With lots of fiddling, messing about with ferrite and two angry children who couldn't watch TV one afternoon I tracked the QRM to the Virgin Media Set top Box TiVo that was radiating RFI into all connecting cables and coupling the noise to everything with a connection to the TV and mains.

I managed to solve the issue with many many windings of all cables and the power supplies onto ferrite cores and the S-meter now reads no noise where as before it was S9+ when near the TV set.

All I need to do now is locate all of the TiVo boxes in and around my neighbourhood to do the same. I hope it makes a substantial difference to the DX receiving potential of my station on the 40m band.

HNY for 2017 and may the Sun Spots keep coming to allow us just a little longer for QRP contacts to remain possible, 73 DE M0TEF. 

Saturday, 20 August 2016

Bringing new life to my station - SDRPlay & SDRuno

I have decided to explore the world of SDR and my first venture into this arena was with the rather sensibly priced SDRPlay RSP at £127.20 including VAT and delivery.

I have been really pleased so far with my experience and even more so that I have been able to sync the new RX up to my existing FT-1000mp Mark V setup to give me a band scope and additional RX using SDRuno software and the Ominirig connection server to share the CAT data with the radio. 


I have already been asked how I have setup the station so produced this graphic to help explain how I set it up. The PC is nothing amazing and is an old cast off from a family member as I usually am a Mac user and wanted a PC to run some basic software in the shack. 



I have made use of the RX antenna in and out from the FT-1000mp Mark V to split the RX and return it to the main radio and send half to the SDR. OK there are some losses but then they are marginal and can be turned on and off using the RX switch on the front of the Yaesu. It allows a band scope on the SDR and also benefits from the same band pass filters used in the main radio to help the front end cope a little better.

Initially I am happy with my results and the outcome, I am also very happy with the added functions to my aging radio setup. 

I hope to get some videos done once I get to grips with the software to get the most from the performance. So far I have found it very good on weak signals for QRP reception. 

Wednesday, 17 August 2016

RSGB field day changes 2017




I have been reading September's Radcom this morning and read that there are changes due to RSGB field day contests. I personally would like to see catagories for small stations and short term ops. Say 8 hours and QRP and battery efforts with additional points for the hard time these stations face. Perhaps similar to the catagories used in ARRL field day. 

I am appealing for QRP users who are RSGB members to support my thoughts and see if we can get a section more supportive of the types of operation we do. 

Here is a copy of the email I sent to Steve  White G3ZVW

Dear Steve, (Steve.g3zvw@gmail.com)

I have been reading about changes to field day contesting and would like to offer my input as a keen field day opp who has given up going out and about. 

I would like to suggest provision in both contests for small short term stations rather like the ARRL field day with a score multiplayer for QRP and battery power alone encouraging individuals such as myself to head out into the countryside for 8 hours or so and join in the fun but be recognised by a score multiplier for the additional efforts required for a basic station making contacts. 

It's just a thought but I have thought for some time we need to be working more like the ARRL field day as it seems to encourage a huge number of small scale entries each year without the need for a major camp and team effort. 

I would like you to be able to pass this forward on my behalf having not been consulted because 2015 was a year I decided the current system was "boring" "restrictive" and "lacking imagination " 

I want to see a raft of low power fun style ops going out and being recognised in their own way instead of being bottom of a table that they don't really fit in. 


Regards

Alistair - M0TEF

[edit - I received this reply to my email...]

Hello Alistair

Thank you for taking the time to e-mail. I'm not a member of the contest committee, so I don't have a hand in making the rules, but I'm forwarding your message to the Chair of the HF Contest Committee (G4FAL). [ 
mailto: nick@totterdell.co.uk ]

vy 73

Steve, G3ZVW

--------

I hope some of you will support and put forward any thoughts you have too. 

Saturday, 9 July 2016

Oh eBay why do you tempt me so...

I was casually looking through eBay looking at the QRP gear and I discovered a Youkits HB1A that was going very cheap indeed. I have a HB1B but thought about a second radio because they are great fun and easy to use. 

All things went well and the radio became mine for almost a quarter of what you would expect them to fetch. Two downsides though, It was from a silent key and had the knobs missing but for the price I thought I'd take a risk. 

The risk was a risk too, the radio turned up and was low on RX and TX power, I opened up the rig and saw instantly what the issue was. The marks of burning gave it away instantly. 


Those of you with a trained eye will spot a rather sorry looking 10uH inductor. Heaven knows what had melted it away but replacing it has left the rig working fine and outputting full power on TX too. Thankfully I had a well stocked spares shelf and a steady hand. I also had a couple of dodgy left over knobs from other projects so please excuse it's Frankenstein's monster type features. 



Was the risk worth it, this time yes it was and I am lucky enough to have a radio that was cheap enough for me to start experimenting and modifying in the near future. 


Sunday, 22 May 2016

Portable preparations


I have been really enjoying working with the you kits HB1B and have used it most days to make a QRP CW contact by the bedside station or out portable. So far I've been using a 12v SLAB as a power source but it has proven to be a pain to carry around with such a weight. I emailed you kits to see if I could buy an internal battery pack and was told this is not possible because of shipping issues. What to do? Make my own...

I found lots of great information online and set about making a 18650 lithium battery pack to put inside the rig but the more I learnt about balanced charging the more I felt this should be a consideration so I also purchased a small PCB from an eBay seller that allowed balanced charging and voltage limit on discharge too. It was not hard to make a pack that charged nicely from 12v and allowed me to fit the whole thing internally. 


Please ignore my messy bench but here is the pack and control board as I soldered all the connections up. I did a dry run on the bench and all looked good so I put the pack inside the HB1B and started to make contacts around Europe. The pack can provide as much as 12.6v at full charge. 

All was good but I needed to make going portable easier, I wanted a nice Peli case but couldn't afford to spend that kind of money on a whim so went looking for what I had stored away to "make do." I discovered an old case that once held spares for my aquariums and soon stripped it down to basics and set about looking for any foam I may have laying about. This is naturally where being a hoarder helps and soon enough I found some suitable foam and plastic to make inserts and set about filling the case and making a secure holder for my basic portable station, the radio, key, charger, ear buds, coax, plugs and antenna. 


Here are a few images to show how I managed to cram everything into a small space and keep it secure. All I have to do now is get out portable and enjoy the summer. 
73 - M0TEF