Saturday, 1 October 2016

MDT40 progress

It has been sometime since I bought the MDT40  (Minimalist Double Sideband Transceiver) kit from OZQRP.

Progress has been slow due to family commitments. But slowly it is now starting to take shape:

Hopefully in a few weeks time I will have it all boxed and complete.

Exciting times - Baofeng DM-5R arrives in the UK.

There has been much talk about the Baofeng dual band VHF/UHF DMR DM-5R recently.

I noticed while viewing ebay today, that one seller now has it available, but only ready out of the box for Tier 1, although I understand it can be easily upgraded to Tier 2. The price makes it even more exciting, at half the price of a single band model currently offered from TYT. Typical of Baofeng to get into the act at the right price!

I am in no rush to buy one yet, as there are very few DMR repeaters in my area, although one is due soon a few miles North of me at Stafford. So for the time being I will just sit back and await the many reviews to appear, before I decide.

Sunday, 21 August 2016

Hand-carried QRP antennas VK3YE

The maestro of the Ham video VK3YE has written his 2nd ebook for the kindle. Peter kindly sent me the details as below:

Summary of Hand-carried QRP antennas

Whether through choice or circumstance, more radio amateurs than ever before are enjoying portable operating. 

Suitable equipment is widely available but what about antennas?  Manufactured antennas exist but only some suit lightweight portable activity.  And, it’s easy to overpay for something that’s too heavy and too lossy for successful QRP.  

Hand-carried QRP antennas takes the mystery out of portable antennas.  After inviting you to assess your needs, it discusses the pros and cons of popular types.  Its style is brisk and practical with almost no maths.

Many ideas for cheap but good materials suitable for portable antennas are given.   Beginners and those returning to radio after a break should especially find this section handy. 

Finally there’s construction details on a variety of simple but practical antennas and accessories suitable for portable operating.  All have been built and tested by the author over almost 30 years of successful QRP activity.  

Hand-carried QRP antennas is an ebook readable on most devices.  It’s the author’s second book, following on from the top-selling Minimum QRP, released in 2015. 


Peter (mis?)spent his youth at rubbish tips, taking apart given radios and TVs and building electronic projects that mostly did not work.  He avoided soldering until figuring out that new solder works better than reusing solder from terminal strips in valve radios.  

Milestones included the construction of a crystal set in 1980, discovering shortwave broadcasting on a valve receiver in 1981 and a simple ‘electronic organ’ in 1982 from a Dick Smith Fun Way book.  Hours were spent putting wires into springs on a Tandy 150-in-1 electronics set.  Amazingly some wires could be pulled out and the project would still sort of work with only half the parts in circuit. 

Two back to back AM/shortwave radios led to the discovery of amateur SSB activity and a novice licence in 1985.  The following year was spent building transmitters no one heard.  A one valve crystal controlled CW transmitter from the 1973 ARRL Handbook provided the first contacts – mostly CW/SSB crossmode on the 3.579 MHz TV colour burst crystal frequency.   The value of frequency agility was an early lesson and various VFOs were built, most of them drifty.  

The 1990s brought more bands, more modes and smaller gear.  Projects included a 7 MHz VXO CW direct conversion transceiver, 2m FM portable transceiver, and a 14 MHz CW transmitter for Cycle 22, then near its peak.  Later favourites included HF DSB and SSB transceivers (often using ceramic resonators, ladder crystal filters, NE602s and BD139 transistors) and phasing SSB equipment.  

Limited space led to experiments with magnetic loops and HF pedestrian mobile.  The joys of the latter (along with the perils of a trailing counterpoise) were first discovered with a converted Johnson Viking CB on 28 MHz.  This was mounted in a carpeted chipboard box with battery and 1.5 metre whip.  A move to a bayside suburb brought further HF portable and pedestrian mobile activity which remains an interest to this day. 

 More details from the VK3YE website

Tuesday, 31 May 2016

BM-800 Mic support group opened.

Due to the intense traffic and interest in the BM-800 Microphone modification, and the amount I have noted sold since the last Blog.  I have opened a support group on Facebook for anyone interested using them for Amateur radio purposes..

Please note this is a Closed group. Anyone can find the group and see who's in it. Only members can see posts.

As well as the the G4IZH modification, it will be interesting hearing your own thoughts and modifications plus any further ideas.  Even if you just run a BM-800 into a simple audiomixer please join the group to help others.

73 Steve

Saturday, 21 May 2016

Really cheap cheap BM-800's!

For those of you who read my BM-800 microphone, G4IZH modification Blog I wrote early April. A UK ebay seller is currently selling the BM800 at a silly price of £6.99 ($10) including UK delivery! These are branded Floureon BM-800 which are the same specification as the 48V ones I have already mentioned, making them ideal for conversion as the details on the link above or for using straight into an audiomixer.

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.

Wednesday, 18 May 2016

Windows 7 says it's last goodbye!

Last night I switched on the PC it booted into Windows 7 as normal, after a quick look around at a few Ham sites I was called for my tea. After returning to my desk after eating my roast beef and Yorkshire puds I returned to something new!

Unknowing to me Windows 10 had downloaded in the background and installed itself on my PC without even informing me. Yes, Microsoft can take over your machine without you even knowing! It appears if you have got your settings set for auto updates it will do this. Beware! Big brother is really alive! Would Microsoft like it if I came in through the back door and took over their servers and PCs, I think not!

I must admit though, there were only a couple of little hiccups which I sorted in an hour or so, everything seems to have gone over clean. It appears you can revert back to your previous operating system but only within 30 days of the install.

Sunday, 10 April 2016

BM-800 Mic something to talk about.

The BM-800 microphone has been around for a few years, search ebay and an abundance of them will flood your screen. The BM-800 and 700 versions are produced in China, the BM-700 version only has slight cosmetic differences but is basically the same. The BM-800 is well constructed for a price of around £10 "including delivery"  putting most expensive commercial microphones to shame for price! Infact you could buy a score of BM-800's to one well known branded studio microphone.

Until recently there were two types of the BM-800 available, one version was badged Shengyue BM-800, this had the advantage of an onboard 1.5V battery to feed the condenser insert. Thus the great advantage of this no external supply was required. This model has now become as rare as hens teeth and we are left with the 48V version. This type however requires an external 48V voltage fed up the cable to charge the insert. Some have overcome this problem using the microphone with an external audio mixer and feeding it using the 48V phantom power supply from the mixer. There is also another problem, the audio output is balanced, and again if not using a mixer you have got to find a method of changing it's output to unbalanced to feed your rig.

I have a couple of these microphones still wrapped up in their boxes and have been thinking for sometime how I could match them straight into my radio's without using a mixer etc.

Until recently there had been very few modification ideas around for this model, but a few nights ago I stumbled across a website from Pete G4IZH  who has not only done all that is required to convert the mic from 48V to around 9V that can be taken from your radio's external mic socket supply, or even using a 9V battery, which could be made to fit inside the BM-800 case. The board has then been hacked, to get rid of the balanced output and then fed directly into a filter to tame the HF and LF response ranges, making it more ideal for Amateur requirements. Of course you don't have to do it quite the same, especially if you want to fit a PP3 battery inside the case a bit more room will be required, but all the information is now there to customize the idea to your own requirements.

Reference G4IZH BM-800 modifications here