Tuesday, 12 February 2019

A Blog a day: The Daily Antenna

While it takes me on average about a month to think up and produce One blog that doesn't bore the pants off someone.

The maestro of the Ham Video VK3YE , writer of a growing Amateur radio book collection, along with his superb website to support his hobby vk3ye.com, has done it again, and now come up with a new challenge a new daily Blog called The Daily Antenna.

The idea is to produce One blog per day on antennas, accessories and related topics.

I don't know how Peter finds the energy and time to fit it all in, but I certainly will be dropping in and reading from time to time, and wish him well with his new venture

I will also drop the link into "My Blog list" on the right handside, because I know it will be a very valuable source of material.

Monday, 31 December 2018

Maplin the end or is it?

2018 was one of the coldest Winters we have had for many years in the UK, followed by one of the hottest Summers, that brought out our shorts, burnt up our lawns, and farmers were talking up the price of food because the drought had caused the yield to fail, so they said anyway?

But the crisis wasn't just down to the weather, the high street was under attack from changing times! Expensive rents, high business rates, the new living wage hike and shoppers that were migrating in droves to the Internet, that were being blamed for causing the end of famous names to quit the towns and cities and made to go bust.

Getting caught up in all this mess was MAPLIN the last electronic major retailer of electronic components, gizzmos, electronic toys and computer components, on the high street. Stores were mainly confined to big retail parks, after they had embarked on a rapid expansion program in the late 1990's.





I had caught a smell of Maplin's demise for quite a number of years before the rumour had ever hit the fan. Everytime I had gone into a store, I kept asking myself how were they surviving, as very few customers could be seen in the stores when I had made a visit? Maybe they did well at weekends, Christmas and holiday time, but every visit I had made hardly a soul was seen? I have to admit, Maplin never filled me with much enthusiasm either, they were expensive! I never really bought much from them, but they were handy, if I was in the area and just short of one component to finish a project one had been itching to get going quick!







This one was the well presented store I visited at Walsall, West Midlands in early February. But already there was a sign something was not quite right, shelves were begining to look empty and not being refilled, the rumour was already in the air.


 
By the end of February the game was up, Maplin was surrendering, the receivers were called in to try and save jobs and stores. How did they get it all so wrong? Whatever Maplin was doing, was already being done, by the likes of RS and CPC for next day component delivery. Or if you were the small constructor willing to wait a couple of weeks an abundance supply can be had from Ebay and Chinese sellers and the likes of Banggood.


Store closurer came quite rapid, nothing could be done to save over 200 stores and all the jobs that went with them, the shutters were finally brought down on the whole operation by the end of July 2018, all was closed, or was it?






Out of the ashes the name survives and has been bought by Dragons Den Tycoon Pete Jones, already the Website is getting ready to run again  and the name is alive once more here: Maplin! 

What will 2019 bring? A Happy New Year to you all.


Thursday, 27 December 2018

G3XBM the PYE PF1 nostalgia

Well G3XBM is always reminiscing about his time at PYE, I wish I could do the same for Thorn Automation days, but as most of the work was restricted very little of their products have made it into the Amateur world. .

Rogers recent ramble here made me reach for the desk drawer. Out I pulled a PF1 receiver still complete with case.



I cut my teeth on a PF1 with my first taste of 70cm receive back in the early 1980's. What I seem to remember I picked  up quite a few of these at a radio rally for about £5 each! But the crystal was about the same price again, which was required to replace the original to get them working on one lonely channel, or tuned up on a single repeater frequency, in my case being Stafford GB3ZI (433.275MHz). What I seem to remember tune up was quite a fiddle, they used to break into oscillation, as the pull was quite a bit out of the zone of where they had originally been working in the commercial world.




 


This one has seen better days, but most of it is still quite complete apart from the metal shield over the front end. The battery was rechargeable 9V long time expired, but soldering in a 3F23 or PP3 would make it burst into life. So as you can see I have been around quite a while to remember the older PYE generation, but not quite as long as G3XBM. :-)


Wednesday, 12 December 2018

One for the Boys or maybe the Girls

When I started in this hobby when I was around 7, it was batteries and old car bulbs nicked from my Dad's shed, with wires held on the terminals with sellotape, that was to give me my first taste of electronics, well before I even started making crystal sets. This is all what is needed, just a little nudge of encouragement to spark enthusiasm in our hobby. Little did I know then, I would have held a job in the industry and have an Amateur Radio licence to my name and I would be writing about it today.


So I was in my local discount store the other day, something caught the corner of my eye, an electronic kit. Tronex 50+ Circuit Lab. Made in, you guess right China! But does similar to what I have mentioned above. Yes it resembles the kits that were once produced in late 70's, where wires were held under springs to connect each component into the circuit.



Only having two daughters, one whom is now married, and the other that is now in her latter years of High school, a chance perhaps to encourage her, and get her away from playing with her tablet and computer during the long hours of these dark nights. So I decided to buy one for her Christmas stocking. My wife said you only bought it so you can play with it didn't you? I said no, this is a good educational tool and can be used to encourage, especially with her having to do a science at school.






Not hopeful she will be another Ham in the future, but you never know where it will lead? For overseas readers of my blog I notice there are Tronex kits on ebay of similar content.

I will return to this when she decides to investigate and play, further info here:

https://www.homebargains.co.uk/products/14749-tronex-50-circuit-lab.aspx


Tuesday, 11 December 2018

Spam will get you no where!


Some idiot today decided to Spam the comment section of my Blog with advert links, nothing to do with Amateur radio, this is not the first time this has happened. So I have now taken action and set all comments to be moderated by myself before they are released. Just stupid people that have caused me to take this unnecessary lock out and create me more work than I need.

Spam as much as you want but they will be destroyed!

You have been warned !

Sunday, 18 November 2018

Far East component suppliers


With constructors and hobbists looking at sourcing electronic components, even the hard to get stuff along with wanting a bit more added value for money.  I have started a component list with suppliers from the far East.


Access it from the top right under Pages: Far East Component suppliers.


Or from this link: http://g1kqh.blogspot.com/p/far-east-component-suppliers.html



Hope you all find it useful?


Saturday, 25 August 2018

The QSX SDR HF from QRP Labs

QRP Labs started design and producing small QRSS/WSPR Beacon transmitters some years ago, along with a complete set of addons and other accessories that have evolved as the project progressed.  Last year, owner and designer of QRP Labs, Hans Summers, took his small company to a new success level with the launch of the QCX 5W Single Band CW/WSPR transceiver. Which has currently sold to date well over 5500 units, over various HF bands.  A fantastic project because it crammed so many full features into it's small pcb, including its inheritance from the WSPR Beacon, but with full frequency agility, CW decoder and included was a unique inbuilt test generator to aid alignment, never seen on such a low price product before.

The QCX has proved a QRP Labs British success story for such a niche product in it's own right.

Of course Hans (G0UPL) wasn't going to rest on his laurels and an SSB radio had been rumoured to be on the design board for quite sometime. Infact he had told me at the begining of this year, these projects takes a while before they hop off the design lab bench and reach fruition to complete into a working project.


So it wasn't no surprise that G0UPL has again used YOTA 2018 (Youngsters On The Air) hosted in South Africa this year, to pre launch the QSX a 10 Band HF SDR project. You could say that YOTA is used like a test bed to iron out any last minute technical and constructional difficulties, found, or encountered, before he begins to put the kit into full time mass production in a couple of months or so. Most of what the new SDR single/10 band rig will do and it's outlined specification, is set out on his website here: QRP LABS - QSX

 Photo G0UPL 



I was fortunate enough to have a short electronic messaging chit chat with Hans earlier this week, and he was able to put me well in the picture with one or two technical details about the project.

While emissions and spurs are all the talk of the town at the moment on another QRP project from another company not associated with QRP-Labs . The QSX will have "no" spuri issues!

Using 2 IRF510's in the QSX's linear HF PA, Hans reports the performance is excellent! The PA module being driven by two BS170's in Push Pull, giving an overall gain of around 26-28dB. This concludes in easily producing 10W across all HF bands using 12V.

Gain Flatness is better than 2dB across the spectrum between 2-30MHz. It is about 4dB down at 6m and 8dB down at 4m.Thus the same drive level that produces 10W across the HF bands gives a very useable 5W on the 6m band.

Hans also reports the linearity is excellent too!

Harmonics are low even before it even enters the LPF: 80m measurements 2nd harmonic is at -38dBc, 3rd -31dBc Making it very easy for the LPF to clean up what remains resulting in a very high performance radio.

All this is achieved using cheap Chinese IRF510's



Photo G0UPL


The heatsink is BIG!! Testing, it ran at 10W output for 1 hour continous 100% duty cycle, no forced air or cooling, the heatsink temperature was still reasonable about 40C over ambient.

Destruction tested at:

1) 20V supply.
2  25W output.
3) 15W 100% duty cycle for 15 mins.
4) Open load.
5) Short circuit.
6) Various mismatches.

All tests resulted in no failure.

Further reference watch the video AE4FH interviews Hans:

https://www.youtube.com/watch?v=hL6CWaY438Y