M1KTA's QRP ham radio blog

Bought a K2

2013-05-13T13:13:00.002+01:00

After building a few for others time I kept one for myself :-) This one already built a while ago...

Not this one although SOTA might be fun... joking!

It will be a 'spare' for DX trips as seems quite a few DX ops like the option of the K2 and it will make a useful multiplier rig or a monitor for other bands.

I will also be building a separate PSU, ATU and a PA into a second EC2 enclosure along with another (no not the KPA100, KAT100 but our own derivatives).

KL500 Modifications

2013-04-28T20:20:00.002+01:00

http://www.rmitaly.com/download/manuals/KL500-manual_rel_500.pdf

I think it should be possible to make a few changes and use it. By keeping the drive below 5W and adding appropriate LPF there should be none of the issues others had seen. Adding some of the ideas for control circuitry from the ARR2012 handbook 250W PA (The one using a pair of VRF151 semiconductor about $37 each on digikey).

This will add over current, over VSWR and over temperature and all three make sense to add.

The KL500 T6 output transformer act as the combiner and the output of this is ideal location for the over vswr protection circuit (T2 from the other design just prior to the LPF). I think it will probably just be a simple signal relay switch that will disable the RF input in the VOX circuitry. It might make some sense to make this a latching type with an override/reset switch. An audible buzzer could be used as well.

The over current I could use the same methodology and add a 0.01 ohm resistor in the voltage line and sample the current across it. The 0.01ohm resistor could be a large 2W version.

Thermal protection. I have a spare 10K NTC thermistor after building a xtal oven for 472KHz transverter and I can add this to the heatsink easily enough.

The KL-500 has a VOX circuit in it so there is no external PTT needed so the VSWR protection I will use to interrrupt this instead.

I might short the AM/SSB switch so the linear works for SSB/CW only and not AM/FM.

The LPF I have a spare PIC-A-Star LPF board and will use that.

QRP OP but been sent a PA for DX trips and a plea to use.

2013-04-28T09:40:00.001+01:00

This is a complex issue but one that I will investigate.

I'd rather do all trips qrp but out of the blue someone send me a PA with a type written note no explanation could I please consider using this next time I did a DX trip (for some of it at least) as they could not hear me. They went on further to suggest it might need some modification before use and suggested BIAS and an LPF.

So I thought time to investigate it.

The PA is one of those built by RM the KL-500. Yuk, nasty horrid CB amp I hear everyone say but I pulled up the circuit diagram and the core it is not that different from most PA's I had seen so I thought I would put any preconceptions to one side and actually test it to see if it might be of any use.

Driven with one of my KX3 that I can wind right down to 0.1W and up to 10W so it is perfect to use as it also contains a two tone test.

So I connected the PA output to a G6ALU VSWR meter and a 1KW dummy load. The input to my KX3. I added between the KX3 and PA and PA and VSWR two samplers so that I could display on a 4 channel oscilloscope the signal in and out of the PA and also sample the frequency spectrum. I meant to take photos but just did this quickly.

The results were interesting.

I do not own a lot of test kit but I have run two main tests one is a simple repeating cw key down sending AAAA and the other is the usual SSB two tone (from my KX3) into the PA. As I mentioned the output from the PA is fed into a (I RF shielded it inside a big tin) dummy load and then sample the output on a spectrum analyser and oscilloscope input and output and see what it outputs. Obviously before going on the air I would start looking at LPF etc.

I tested the amplifier on the bench briefly after chatting to someone else with a pass through (you will find a circuit for one on this blog) to a big dummy load and a sampling and used a cheap Vellemann spectrum analyser to evaluate the out of band signals up to 25MHz and an oscilloscope (tektronics 4665) to monitor the input and output. I was pleasantly surprised to find the results seemed fine from 3.5 to 14MHz and harmonics (that I could see) were more than -45dB down at least as long as input drive power was 8 Watts or less, I'd normally be closer to half that however if more was used (KX3 will go to 12W) the amplifier started to go non linear and produces lots of harmonics. No surprises (for me anyway).
I measured the RF voltage directly at output and used a G6ALU VSWR meter for some of it and the power output, with 5 Watts drive manages over 80-90W and with 10 Watts drive >240W output on some bands it is not quite linear over the whole range but close (might be down to my quickie measurements), there are 6 power settings and the output appears to be much better with lower drive. Current draw at maximum was close to 34 amps ouch! and there is a lot of heat after a while but I suspect would be reduced at lower output. Adding a 12V 4" fan cooled the PA well. The final power transistors according to data sheets are capable of 80 Watts each and therefore the max power out as there are 4 should be 320 Watts if in parallel.

It is not that heavy 1.5KG and was free, albeit I might have to put in some effort and some components to get it to work so maybe an option

I know about the fact that on AM these things fail (google search) and as the PA have no VSWR protection you need an ATU or resonant antennas. So might be time to add in the VSWR protection circuit I put together in 2009 as the transistors are, like most in PA, not free of wierd effects if the VSWR goes above 3:1
http://m1kta-qrp.blogspot.co.uk/2009/11/lm3914-and-swr-and-protection.html

I would still have to figure out what could I use to power it as it is not like you can plug into a mains outlet when you are on a DX beach and I suspect a car battery but I'd be prepared to stick a car battery charger in the luggage and source a car battery locally.

I'll run through tests again after I have added a fan, an HF LPF and a switchable BPF and the VSWR protection circuit and post some images.

It was a version that has the BIAS modification already performed but I will do the triple fuse to single fuse swap out.

I did some on air tests this w/e and one evening during the week (with an LPF in place) CW only and boy does a 200W signal go a long long way! Thanks to those stations that I contacted and allowed me to wind the power up and down from 5w to 150W and were able to clarify my thoughts that 5W was not always audible, but as qrp fans we already know this, 20W was usually heard if not always understood, between 50-80w 85% copy all the time even with QSB, 100W+ reliable copy even if deep QSB on band.

I guess I need to find a real DX station to test this with whilst having an antenna on the beach and do some field strength measurements too.

I did not notice any 88-108MHz FM radio interference or TV (mast head pre-amp) interference once LPF used (-70dB cut off at 35MHz). Which is what locals would complain about most I suspect.

CEPT Operating in Greece - it is allowed even if you have a no code licence

2013-04-11T14:41:00.004+01:00

Until recently if you had a full or intermediate UK licence but you had not passe an official CW test as part of the licence requirements you were not able to operate on HF under CEPT in Greece.

Plenty of how do you operate in other country sites also mentioned this was the case.

This changed recently but the details do not appear to have filtered through.

I just confirmed this with both the President of the RAAG (Greece RSGB equivalent) Manos SV1IW and with IARU a pass in a cw test is no longer a requirement for operating HF in Greece under the rules of CEPT. So if you have a full or Intermediate licence you can operate on HF, Novice M3 and M6 are not valid under CEPT.

The comment by email I have from Manos is:

"You will only need your U.K. License with you. Depending on the place you visit you may use the call SV1/M1KTA/M or SV1/M1KTA/P or any other SVx/M1KTA/P. For your convenience I am sending you the current radio regulation document for radio amateurs in Greek. Pages 11 and 12 (articles 22 and 25) describe operation in Greece for visitors. I would suggest printing it and carrying it with you..... Power for HF is 500W PEP and 100W for VHF-UHF".

For any that cannot find it and are planning to visit if you ask I will send you a full copy of the Greek radio regulations. Article 22 and 25 are included below.

Άρθρο 22
Κάτοχοι αλλοδαπής ραδιοερασιτεχνικής άδειας
που εκδόθηκε σύμφωνα με την Σύσταση
T/R 61−01 της CEPT.
1. Κάτοχοι αλλοδαπής ισχύουσας ραδιοερασιτεχνικής
άδειας που εκδόθηκε σύμφωνα με τη Σύσταση T/R 61−01
της CEPT και τούτο αναγράφεται−δηλώνεται επί της
αδείας, έχουν δικαίωμα λειτουργίας ραδιοερασιτεχνικού
σταθμού σύμφωνα με την αντίστοιχη ραδιοερασιτεχνική
κατηγορία της αλλοδαπής αδείας τους, κατά τη διάρ−
κεια της προσωρινής παραμονής τους στην Ελλάδα
και όχι πέραν των τριών (3) μηνών, χωρίς να απαιτείται
έκδοση Ελληνικής άδειας.
2. Στη διάρκεια της προσωρινής παραμονής του ο ρα−
διοερασιτέχνης κάτοχος αλλοδαπής άδειας που εκδό−
θηκε σύμφωνα με την CEPT T/R 61−01 μπορεί να εγκα−
ταστήσει και «σταθερό» σταθμό, χωρίς να απαιτείται
έκδοση Ελληνικής άδειας. Ωστόσο, στην περίπτωση αυτή
εφαρμόζονται οι τεχνικές διατάξεις που ισχύουν για την
εγκατάσταση ελληνικού ραδιοερασιτεχνικού σταθερού
σταθμού, συμπεριλαμβανομένων κατά περίπτωση και των
διατάξεων αδειοδότησης των κατασκευών κεραιών.
3. Στους κατόχους αλλοδαπής ισχύουσας ραδιοερα−
σιτεχνικής άδειας των παραπάνω περιπτώσεων συγκα−
ταλέγονται και αυτοί που προέρχονται από χώρες που
έχουν αποδεχθεί επίσημα τη Σύσταση T/R 61−01 της
CEPT και επιπλέον οι άδειες τους είναι ισοδύναμες με
τις άδειες της υπόψη Σύστασης. Στις περιπτώσεις αυτές
δεν είναι απαραίτητο τούτο να αναγράφεται−δηλώνεται
επί της αδείας. Η Κεντρική Υπηρεσία του ΥΥΜΔ, μεριμνά
για την ανάρτηση πίνακα, στον ιστότοπο του Υπουργεί−
ου, με τις χώρες που αποδέχονται τη Σύσταση T/R 61−01
της CEPT καθώς και λεπτομέρειες σχετικές με την ισο−
δυναμία ή όχι των κατηγοριών των ραδιοερασιτεχνικών
αδειών που εκδίδονται από τις χώρες αυτές.
4. Στην περίπτωση που ο ανωτέρω αδειούχος ραδιο−
ερασιτέχνης, διαμένει στην Ελλάδα πέραν των τριών
(3) μηνών, δύναται να ασκεί τις ραδιοερασιτεχνικές του
δραστηριότητες μόνον εφόσον λάβει Ελληνική άδεια
σύμφωνα με τις διατάξεις του παρόντος.

and

Άρθρο 25
Λειτουργία ραδιοερασιτεχνικών
σταθμών αλλοδαπών στην Ελλάδα.
1. Η ισχύς εκπομπής του ραδιοερασιτεχνικού σταθμού
αλλοδαπού καθώς και οι συχνότητες λειτουργίας του,
σε καμία περίπτωση δεν υπερβαίνουν τα όρια ισχύος
και τις ζώνες συχνοτήτων που ισχύουν στην Ελληνική
νομοθεσία.
2. Εάν ο αλλοδαπός ραδιοερασιτέχνης μείνει προ−
σωρινά (μέγιστο χρονικό διάστημα τριών μηνών) στην
Ελλάδα, λειτουργεί τον σταθμό του εντός του Ελληνικού
ραδιοχώρου χρησιμοποιώντας το πρόθεμα “SV” ακολου−
θούμενο από τον αριθμό Ελληνικής ραδιοερασιτεχνικής
περιοχής, ακολουθούμενο από το δικό του χαρακτηρι−
στικό κλήσεως, ακολουθούμενο από το /P ή /M ή /MM ή
/AM κατά περίπτωση. Ο υπόψη ραδιοερασιτέχνης έχει
δικαίωμα χρήσης ΕΔΚ σύμφωνα με τις διατάξεις του
παρόντος κανονισμού.
3. Ο αλλοδαπός ραδιοερασιτέχνης που μένει προ−
σωρινά (μέγιστο χρονικό διάστημα τριών μηνών) στην
Ελλάδα, δεν δικαιούται προστασίας έναντι επιβλαβών
παρεμβολών σύμφωνα με τη Σύσταση T/R 61−01 της
CEPT.

This does mean that any operations that were undertaken in recent times (2003 to date) might not all be valid for DXCC or RSGB IOTA credit I would advise that you check if the station operation was valid.

Homebrew desolder braid

2013-04-11T09:35:00.000+01:00

I have some lengths of ratty RG-213 and RG-8 that I pulled the core out of and use for all sorts of hook ups and I use the braid for desoldering, you should 'treat it first'. My Dad (67) showed me this a while ago, he located a tin (looked a bit like neutral boot polish) of flux paste, not plumbers stuff but that can work too. You paint the braid with the flux and warm it to let it run through the braid (don't heat really hot so it smokes) and let the excess flux dip off. Then allow the section (12" lengths) to cool down and put them in a plastic bag. When need it you use as if it were 'proper desolder braid.

It saved a fortune and who has not got random old lengths of coax ?

You could use almost any coax but the ones with untinned copper braid is best, using RG174 will give you fine braid but even TV coax braid works.

If the braid is green and horrid it doesn't work as well:-)

OT radio wise but a common enough occurance for amateurs laptop or PC drive failure

2013-04-11T09:10:00.000+01:00

Some of you probably know how to do this anyway… but I suspect a few will have a laptop or a PC in the shack and this might help you figure out options...

A friend's laptop runs windows 7 and it started alerting that the hard drive was going to fail so could I help? They brought it over and sure enough smartdrive reports failure imminent. So I bought a couple of new drives, same model and size off ebay, I knew what these were by going into the BIOS, no point trying for a system restore with restore DVD as 100% positive they will have installed stuff (SDR, HRD, Winlogger, Skype, Win-Test etc...) after they bought it that I know nothing about and I might spend endless hours trying to put it all back together again.....and as the system is working albeit a bit slow right now.

So first I shutdown and remove the 2.5" drive from the laptop and put it into a freezer bag and into our freezer over night. The following day then boot laptop using a damn small Linux live CD, with new drive in place did not format it or anything just take from static bag and fit it and put old one (it was at -18C initially) in an ebay cheap usb3 external enclosure with the cover off. The BIOS sees the new drive then booted into Linux and ran ‘dd if=/dev/sdb of=/dev/sda’ nice and simple one 320gb drive cloned to the other and they get old system back …. However this can take a while so how do you get feedback from dd?

If I run the dd command in one terminal then open a 2nd terminal and run ps -ef | grep dd and find the ..... then run 'watch -n 100 kill -USR1 ' and you get the progress. updating every 100 seconds in the first window.

I also wrote up instructions how once a month when there are a couple of hours when not using it insert the live cd and the usb drive with the second drive, reboot the system and run the dd command and the feedback in two terminals so creating a clone of the original drive. As the clone drive is formatted as windows they also have the option of seeing the files they created by plugging the drive into the laptop, they can use it but it will be wipped every time they clone the drive in the laptop which is fine. At least if the drive fails again I’ll have a drive ready to go too.

The freezer bit… old habit if a drive was failing it often helps to hard freeze it (dry so have to protect from ice) before reading it one last time. It was still cold after 2 hours (which is about time it took to run the copy).

Smartdrive after the copy says it is due to fail so I'll scrub it.

TNT Tx moves a stage closer

2013-04-07T14:31:00.001+01:00

Closer to building the TNT (lots of details here http://members.shaw.ca/ve7sl/tnt.html)

At CRG rally this morning found these...

The bases are fine with no cracks and two of them include the top brass nut. The threads on the brass threaded bolt look like some old BA gauge so will need to rummage to find a spare. However, I can see I could replace them with a 'new' M5 brass bolt as they are slot bolts and that can be seem from underneath. I do not have any thumb nuts which appear to be used with the original to adjust/swap the coils so I wil have a think about that.

I had a chat and I managed to locate some fibre washers as they will have been use originally to secure these to the base.

Two reels of air conditioning coolant 1/4" OD copper pipe for the coils were delivered yesterday. The wall thickness is more than brake pipes which are also a Nickel Copper alloy.

This means I will have plenty to make 80m, 40m and perhaps 20m coils. I do not think the original were ever operated on 30m but I might make up a 30m coil set.

I have variable caps that will suit, and I will use a broadcast 500pF type in series with the antenna output as I suspect will use typical 50ohm antennas at QTH initially

A bag of lozenge caps and a couple of vintage grid leak resistors make up the rest of the components along with some paxolin based 5 pin sockets (I will have '27 tubes) were a donation from another amateur. I have a backup porcelain UX-5 base as well.

At the Borne Airfield market on Easter Monday I picked up a nice cheap wooden broom handle that is the right diameter for the grid coils that I will cut down. I'll use some of the same varnish on them that I used for the workshop worktop which is rock hard now. And I have some long bolts I will use to connect them into the circuit if I do not use these little stand offs.

Several have commented that the HT should be shunt fed which is what I will do.

The PSU transformer I might wind one specially for it but I have some 'glowbug' type transformers with an almost 1:1 mains 240V to HT so I could use a voltage doubling circuit and there are separate filament windings.

GQRP Valve day is 21st April... lets hope can get it on the air in time.

Sussex Valve Tester construction so far

2013-04-06T18:30:00.000+01:00

Just stuffed the PCB based on Mike Rowe's layout.

Some of the PCB transistor layouts seemed to be reversed and TR8 was definitely needed to be 'tweaked'.

I also have one of Ed Dinning transformers so I will not use the 35V on board transformer as the transformer has the windings in it.

The rest of the Rapid order has the other components. I'll start panel bashing soon... I think might make it into an A4 (ish) size flight case so it can be closed up and carried easily.

Paraset panel

2013-04-04T14:00:00.003+01:00

Ran into Geoff Wilkin G0DDX last night at camb-hams pye and pint , white horse in Barton.

He has fabricated a number of laser cut panels for wooden box type parasets.

Similar to this one.

I'll make one up from bits I have.

UT60A DVM as a frequency counter

2013-04-01T16:37:00.000+01:00

Very quick demo of the DVM used a as a frequency counter.

It is not hyper accurate with lots of digits but it does work.It will give 10KHz resolution above 10MHz and 1KHz below... it will go down to audio frequencies as well but not got a video of that.

Oops... forgot CQWW WPX contest was on

2013-03-31T14:17:00.000+01:00

Well antennas work but forgot the CQWW WPX contest was on... bit of a nightmare trying to work DX qrp with a contest on :-)

The dipole is OK on 20m and 15m and very easy to change bands.

Initial quick test shows this is for 15m, 20m and the others are better.

Homebrew "LoStRoPo" Portable dipole

2013-03-30T19:14:00.001Z

Going to the beach tomorrow brrrr... yes will be cold.

I have my vertical dipoles that I have had fun with in KH8 but I always wanted to build a /P multiband dipole where the 1/2 element is made up of resonant sections that are switched in or out. 10m,12m,15m,17m and 20m.

The lengths of the sections on each arm (so you need two of each) were (I had to do a bit of pruning to get it all resonant band at a time). 10m to 20m so this is from centre out...

254cm, 32.5cm, 52cm, 56.5cm, 112cm

There are multiple ways to connect the sections but I figured that probably the most effective was to make a dipole that was for 10m and then to add a section for the next band prune and move onto the next one, the connections between the sections I will be using Anderson power poles (as I have just located a small bag). They 'remake the connections each time so the antenna should operate fine.

I have included strain relief using some freebee credit card sized cards from Love Film (used two), Starbucks (used one in the end insulators) and Rohan (two for the dipole centre, the wire was from a reel from poundland which was twin copper and stainless steel, I only want the copper so I unzipped it (I could have left in for added strength but I wanted to see how light I could make this, and it still work. Right now the 10m of RG174 weighs more than the dipole elements.!)

I have called this the LoStRoPo multiband dipole.

Sotabeams kindly provided a couple of winders and the dipole arms fit nicely.

I used RG174 and some liquid tape on all the centre connections (again sotabeams).

I used some braided yellow string on the ends.

Will see how it does tomorrow....will be set up as an inverted V using a 10m pole or as a vertical dipole I will use alongside the kite antenna with the KX3.

I add photos and VSWR plots later.

Kite flying again...

2013-03-30T15:20:00.000Z

More wind today so tried attaching the heaviest long wire I had just to see ...

and it lifts, then it doesn't and floats down again, then it goes back up....

Finally wind takes it...

Climbing...

That is 50m of line, 41metre long wire and angle of kiteline and wire hanging beneath it is about 60 degrees.

.... stays up for 25 minutes and then floats down as almost no wind.

The kite is held in place with 200lb braid attached via a carbineer and a sling to a dog tether. The Antenna wire is also attached to a separate dog tether, the line between the two with the red cylinder is a static discharge line that has a 4mm stacking plug at one end and croc clip on the other.

No radio connected but just wanted to test the setup.... was a bit anxious as low wind but once the kite caught it... up up it goes.

Note the leather gloves these are 100% essential even in light wind the line can cut through flesh very fast! By the performance today in stronger winds (hand held anemometer coming) this kite will generate a lot of lift.

Off to the beach tomorrow with a backup antenna to test out 80m and 60m with it.

qrv on 60m :-)

2013-03-29T17:00:00.001Z

Three quick qso M0AFJ, GM3WUX, G3OGP

Lot of back ground noise

Almost no wind...

2013-03-29T15:15:00.000Z

The major problem with a kite antenna... no wind no antenna.

It got to about 10 feet AGL (no antenna connected) but came down again.

Still it looked good and the angle was steep.

Need a constant wind.

Wil go to beach tomorrow with 'normal' antenna too.

Expect to be qrv 15m, 20m and maybe other bands if the antenna goes up.

unun for the kite

2013-03-29T10:13:00.002Z

Made up a unun for the kite.

I am afraid not terribly scientific just a current balun. I just grabbed two colours of 18swg enameled wire (the enamel comes off under extreme heat) and a T200-2 and bifilar wound about 23 turns on it. I known that the more turns then 40m and below 'likes it'. I wrapped the T200-2 with electrical tape first.

There are loads of circuits on the web for an unun so I'll not repeat it here.

RG58 was used and I had to fiddle a bit to get it to fit, without prodding it about. I used some random terminals.

The RF ground side is bonded to the tin in several locations.

I'll have a separate antenna wire to ground lead, croc clip with some megohm resistors in as a static bleed.

The tin is a Swiss lozenge tin from 2007, yum finished thee sweets first then washed out the tine with acetone. I like these they are same size as an altoid but twice the depth so a T200-2 will fit. The card on the base is from Starbucks one of the olympic 2012 cards they had at the time I pick up a few every time I visit as they are useful for all sorts of insulation tasks and they fit the bottom of the tin.

As I expect will get a bit of use/abuse I have hot melt glued stuff together.

The matches an unbalanced antenna to an unbalanced feed no transformations.

Kite

2013-03-28T14:14:00.001Z

It has arrived, it has arrived.... try to imagine jumping about all excited. Who said grown ups cannot act like a kid from time to time...

I have been messing about with flying antennas on the beach from a kite for a bit with mixed success and though it was time to get something a bit better and bought one of these. It has a 6 foot span and seems to be a decent single line kite.

I have also taken advise and bought some Superbraid electric fence braid (keeps sheep in the field type) which is 6 x 0.2mm tinned copper conductors within a monofil polyethylene rope. So it is strong AND it doubles up as the kite antenna. Must remember leather gloves though.

Easter w/e so I am sure I'll get up to The Goggs close to where I live or maybe the beach near Kings lynn and have a play.

I might even take the KX3 along.

Going to solder a series of 1Mohm resistors across a piece of PCB in a small box with some terminals to act as the earth leak circuit between the antenna wire and ground BEFORE it goes near the KX3 to provide a static discharge.

Where did I get it...

http://www.kites4you.co.uk/contents/en-uk/d45.html

Old valve bases

2013-03-27T19:44:00.001Z

I recently asked on GQRP if anyone had some old (1920/1930) 4pin or 5 pin valve bases.... I was asked why...

http://members.shaw.ca/ve7sl/tnt.html

I am building a 1929 replica TNT TX but will be shunt fed for safety so will not have 500V on the coils so not quite 1920 style :-)

The tubes are early triodes type 10, 27 or 45 the 1st and last are 4 pin the 27 is 5 pin. The full numbers should be UX-210, UY-227, UX-245 the sockets I think were known later as UX4, UX5... the 'correct ones' I need (saw them at Dayton 2008 in flea market for 25 cents and I could kick myself now for not buying them) are about 1 1/2" square base with a black central cylinder that the valve plugs into.

Finding a tube let along a working one from 1920's is hard enough, and I have someone from US that has found some of each for me... old globe style not shoulder ST so it should have the vintage feel :-) I have some '27 arriving soon.

I have the sprague lozenge capacitors, 1/4" copper tube, resistors (fabricated something) and the variable capacitors (I think they might be WWII vintage so a bit new but they are the right sort hihi)... but cannot seem to locate the valve bases or a couple of beehive insulators for the coils so I will fabricate some from a block of PTFE and paint brown until I can find originals.

I even have some vintage 1920's style QSL cards using the same orange/red, card stock.

Even though I have a modern call they 'look' like from an old experimental station. Power should be c2W so perfect for qrp and perhaps GQRP winter sports or one of Colin's G3VTT valve days.

The power supply will be a simply transformer with another type 27 valve used in it.

Makes a change from all the silicon stuff in the shack and workshop.

Telepocket 600 6m poles

2013-03-16T18:24:00.002Z

I was sent an email that asked for some more details on these ...

I showed a pair of these at Rishworth 2012 as I use them /P and on trips. The interesting bit is that they are only 580g and collapse to 0.58m so they fit in normal airplane carry on luggage (OK you have to put them diagonally in your bag but so what! I fit them into the Aluminum case I use for my /P radio kit on trips)

http://www.decathlon.co.uk/telepocket-s-600-id_8044451.html

They seem to have gone up a bit since I bought mine at £9.99 each now at £12.99.

The manufacturer website is http://www.caperlan-fishing.com/EN/telepocket-s-600-54683455/

They are great for 20m-10m verticals and can be used and this starts to become a compromise antenna from 30m, 40m and on down to 80m with base loading and can take a dipole or long wire (I use a W3EDP with mine) if the wires are not heavy the top sections will bend a lot otherwise!

Check out http://www.nonstopsystems.com/radio/frank_radio_antenna_80m_vertical.htm whose webpage put me onto using for 80m intially. My base loading is a lot less elegant and is usually using whatever plastic drinks bottle I can find and a KD1JV Deluxe Antenna Tuner http://www.qrpkits.com/deluxetennadipper.html and a couple of tap points to get the vertical approximately resonant.

You will need a tuner (AMU) to operate and a couple of radials. I use a couple that are made from two sections of about 11m flat ribbon cable which have the wire left in situ but cut out for 10cm or so for resonance at the CW end of 40, 30, 20, 17, 15 and 10m). The ribbon cables are 8 wire I have the outer two resonant at 14.275 and 21.275 (The later was using to good effect in 6W on AF-045).

If you can it is better to have the radials RAISED at the feed point and the ends tapering to ground. Not 100% sure of ther theory but experience says this does make a difference. The RX signals and reports tend to be better in the direction of the radials. I often do not put them out 180 degrees apart and the antenna is more of an L with two legs if that makes sense.

The two radials could (but I have never used them for this) be used as dipoles.

I was asked how I secured them... well I have become a fan of some plastic ground screws but I have also found that you can use patio table parasol bases. Beaches often have these somewhere.

RSGB BERU Antenna farm :-)

2013-03-09T14:18:00.001Z

I will only be having a go today so not even a 12 hour entry and qrp with kx3 but I have put up a few antennas.
The two vertical dipoles from KH8 on 15m and 20m along with my qth vertical 10-80m and thee 140ft long wire that will tune most bands.

The antennas all come into the shack though the window with coax balun on the two dipoles.

The 140ft long wire comes down over the 4" pipe off cut into the window.

Not huge number of contacts 15 (11 on 15m, 4 on 20m) in first 2 hours all uniques 2 HQ stations and 11 DXCC. I have heard some VU, VK and ZF2XF but have not worked them yet.

On hour lunch break :-)

Given up on RSGB BERU... sat in queue waiting to work VY2SS for 30 minutes no fun!

poles I brought back from KH8 that were busted

2013-03-07T16:14:00.000Z

This is just the base sections.

'Not possible to work DX with QRP... then how about this?'

2013-03-05T08:56:00.002Z

Not just me doing the QRP thing on the beach and if you want to know what it is capable of this is an exchange I had with Pete M3KXZ.

On 03/03/13 11:08, Pete wrote:

I was a little late getting going this morning, thanks to bad night's kip (dodgy back!). But, I finally managed the 2 minute drive to Rottingdean Beach with the dogs and got down there at 0830UTC.

Set up the gear by 0840UTC and tried to find VK6PTU and G6UOI who I was hoping to meet around either 14220 or 14185 but no luck.

Heard VK6LUD on 14235 in convo with a G. Also heard VK2CR in convo on 14180.

Kept listening back and forth between the two.

As soon as VK6LUD finished, I pounced and we had a great 10 min QSO from 0846UTC. Rob was pretty gobsmacked when I told him I was sitting on the beach and running 2.5W into a vertical whip. Smashing - I was dead chuffed.

Now properly stoked up I heard VK2CR signing off from his QSO and did the same. Tail ended the QSO and ended up having a great chat with Peter (GREAT NAME!!) at 0900UTC. I was 53 to him in Sydney and he was a good 59 back to me. Again, amazing. 2.5W :)

My head was now spinning. On 14218I heard VK6WC just finishing a QSO and again.

I pounced and tail ended it. Another fantastic QSO at 0906UTC.. Reports again 53 and 59. Wicked!

After this half hour I was feeling a bit chilly and needed to get the dogs home.
I had one final QSO with IZ0VXY/P who was activating the castle Castello di Prossedi.

FANTASTIC half hour trip. 2.5W SSB on 20m. Still grinning now :)

73
Pete M3KXZ
GQRP 11767
SKCC 10219

On 3 March 2013 15:25, Dominic Baines wrote:

That salt water thing really works :-)

Vertical on 20m what radials, raised or just laid on pebbles (know you have not got sand).

72
Dom
M1KTA

Hiya Dom.

It was just to simple to set up - just fed the 5 metre tall whip against a 3 metre long counterpoise wire that just sat on the ground. Tuner right at the feedpoint to match it to the coax, matched easily and off I went! Also easily matched on 40, 30, 17, 15, 12 and 10 using the Elecraft T1. No balun/unun this time - just used one of the BNC to terminal adapters that I got from G3CWI. Tripod is carbon fibre so isn't too worried by salt water.

Here are some pictures. If you look carefully you can see some sand!

The white wire is the counterpoise.

View of the whip. Slightly wonky horizon in the background, and on the right hand side is Brighton Marina just poking into the sea.

My pile of /p stuff. Antenna rods go in the canvas holder, LiPo batteries and charger go in the ammo tin and all the other stuff goes in the orange dry bag.

Rig showing received sigs from VK2CR. He was peaking over S9 as were the other two. I really need to get a phone with a decent video recorder and would love to be able to record QSOs like this.

The VK QSOs were at 2.5W and were LP - work out at well over 6,000 miles per watt. The CW CQ I made on 14008 at end of my session was picked up by AA4VV in Lexington, North Carolina. Distance approx 4,000 miles SP. Amazing thing is, the CW CQs I made at 100mW so that's 40,000 miles per watt :)

Absolutely terrific little session!

The trousers in the last picture are current army issue lightweight goretex in the latest multicam design - brilliant for /p :)

Hope all well with you.

73

Pete M3KXZ
GQRP 11767
SKCC 10219

Dom, Just realised a mistake in my power out for the CW CQs.... or course low power is 500mW, not 100mW! So only 8,000 m/W - oh well.

I'm toying with the idea of altering the power out on low setting, or maybe building a 10dB attenuator. Some good info here http://a29.veron.nl/pa1b-06.htm

73

Pete M3KXZ
GQRP 11767
SKCC 10219

On 4 March 2013 06:40, Dominic Baines wrote:

Brilliant photos you blogged these anywhere? If not do you mind if I write a post on mine and add them with your words?

I just love the idea of beach qrp as we both know it works and your setup is great and looks so simple.

I am sure you had loaded that mass of sea weed to the South hihi...

The whip where did you get that and the coax looks like same source as the pants you can almost see a MOD number :-) ?

72

Dom
M1KTA

Hi Dom.

I've never got round to setting up a blog, and not sure when I'll get a chance to, so please feel free to post everything on yours.

Do you think it might be worth while measuring the effectiveness of the SWRFAS (seaweed RF amplification system) and then marketing it to those who live inland? Perhaps even look into profitable sales to the MOD? Hmmm, you've got me thinking....

The whip and the coax leads I use all came via various sellers on ebay. The leads specifically from G4LOO but I can't see he has any listed at the moment. Army Radio Sales stock plenty of this sort of thing and the prices are reasonable for good quality stuff. I tend to just keep an eye on ebay though for anything I fancy. Melchior762 sells some brilliant earthing straps that I've use in my vehicle! my Mrs goes nuts though because all this mil surplus gear keeps turning up. I've even got a mil surplus Sankey Wolf trailer that I use for when we go camping :)

Pete M3KXZ
GQRP 11767
SKCC 10219

CDARC Rally

2013-03-03T17:20:00.000Z

Attended this today and saw a few old friends and had a few pop up and say hi. Apologies if I did not immediately recognise you.

Picked up a copy of SPRAT Book from RSGB stall. Steve 9M6DXX has done a great job. It is a really nice read.

The designs include some 'classics' but the book does not mention that some include obsolete or 'hens teeth' components that might challenge the constructor.

Load of directs to 6W/C5/KH8 just went out...

2013-03-02T11:46:00.001Z

I had most of these on the buro pile ready to go out.

CT7/M1KTA diary so far

2013-02-27T13:48:00.001Z

10/2/2013

Ilha Deserta
Island south of Faro

IZ8TDP 15:25 SSB RX 57 TX 59 21.262
W9FFA 15:29 SSB RX 53 TX 59 21.260 Bill QSO??
4U1GSC 15:37 SSB RX 57 TX 59 21.252
G4NVY 15:56 SSB RX 51-57 Deep QSB TX 59 18.142 Mike 110W Gloucester, amazed by QRP signal
kept cq cq cq batteries low... dropped to 3W from 5W
G1UKZ 16:10 RX 21-53 Deep SLOW QSB TX 59 Phil 100W Manchester TS850 Loop antenna, also amazed by qsp qso.

Missed OX3MC, M1AQD, 7X5JF all 14.260-14.263...

batteries died. QRT 16:25