latest ham radio projects

Clark Scam 12 pump up 40ft / 12m mast Feb 2015

I have just picked up a Clark Scam 12 mast and want to get it installed on the bottom corner of my garage. I have loads of bits with it including 2 types of base plate's 4x support legs various guy lines a hand pump and a small electric compressor. I will get photos of all I have over the next few days and then work out how I am going to mount it. Here is a stock photo of what I have.

Clark Scam 12 pump up mast

The Clark Scam 12 mast is a military grade pump up mast that is a proven design and used all over the world as ground mounted and fitted to military vehicles. Over time many of these Scam 12 masts have come onto the 2nd hand market and can often been picked up on Ebay for around £400 for a working one and sets of new seals can still be got from Clark Masts Limited to bring a old one back up to spec. Clark Masts are based in the Isle of White in the UK and make many pump up masts, wind up masts and push up masts.

Sirio Gain Master ham 10m GainMaster May 2013

Going to give this Sirio a try on 10m, the spec seems good so looking forward to putting it up. The Gain Master is now up and working very well.

Sirio Gain Master antenna

download pdf
Gain-Master™ installation manual
(pdf file, 2270 kb)

Sirio Gain Master whats insideSirio Gain Master coil and mounting

the RF signal starting from the generator run through the coaxial cable of the choke coil, then continue along the first part of the whip until it meet the coaxial stub that works as impedance matching, and then continue up to the termination of the coaxial line (antenna phase centre). At this point, the signal on the inner conductor crosses the capacitor and propagates along the upper half of the radiation element. The RF current travelling inside the cable shield, protruding outside the screen and descend toward the choke coil where the high impedance stop it (in fact, it's equivalent to a centre-fed dipole).

Where to buy Gain Master in UK "click here"

Type 0.625 λ center feeded vertical dipole
Frequency Range @ SWR ≤ 2.0 25.5 - 30 MHz 400 CB channel & 10m ham band
Impedance 50 Ω
Radiation Omnidirectional
Polarization Linear Vertical
Max Gain on the horizon 1 to 2 dB higher than conventional 5/8 λ
Max Power 500 Watts (CW) continuous, 1000 Watts (CW) short time
Ligthning protection All metal parts are DC-grounded, the inner conductor shows a
Connector UHF-female, PTFE insulator & gold plated central pin


CapCo 80m-160m Magnetic loop Jul 2012

I just got myself a Cap.Co 80m - 160m Mag loop I think it is the CAPCO AMA-4. It looks small on the ground but it's 12ft across! it was painted green by the last owner so it would blend in.

In testing the CapCo AMA4 that the tuning is very hard and I am thinking of fitting a stepper motor for a more fine tuning. I would like to hear from anyone that has fitted a stepper motor to a CapCo magnetic loop.

Caoco magnetic loop 80m and top band AMA-4
testing capco magnetic loop

Here is a photo of the big cap but will be upgrading to a vacuum cap

CapCo main tuning cap

As you can see the motor at the end has broken off due to the loop falling over so I will take this time to look into fitting a slower gearbox. Also the 6 inch pipe got damaged so this will also need replacing.

CapCo 6 inch pipe cover for the main cap damaged

Close up of the motor and gearbox mounting after temp repair

CapCo 6 inch pipe cover for the main cap damaged

And the Capco controller, looks like I will have to make a new front for it as it seems to be card and messy

CapCo magnetic loop controler AMA-4

So far I have not been able to find much infomation on this magnetic loop, I think it is the AMA-4. HERE is a PDF file I have found of testing of the CAPCO AMA-5. I hope to get the capco magnetic loop installed this weekend 4th May 2013 at the top of the garden away from the shack. I have found next to the shack it was picking up noise from the 6 pc's !

Antenna work Jan 2012

Spent the day installing a new Kenpro KR-800SDX (Yaesu G-800SDX) rotator on the tower as my old KR600 had a few problems. At the same time I have also put up my Comet 422V on top of my KT34A in a V configuration along the boom.

Kenpro 800SDX Rotator / Yaesu G-800SDXComet H422v rotary dipole

I have also picked up a 2nd hand Capco 80m / 160m magnetic loop that I need to get collected and I will fit this on T&K brackets on the side of the shack, the loop is 12ft diameter.

View from front of house KLM KT34A HF Beam

Tower showing KT34a and 422v from front of house

View from garden Comet 422V rotary dipold for 10/15/20/40mtr

Tenna mast tower with antennas garden view

View from back of house showing Tenna Mast with all antennas

Tenna mast Tower with new 800SDX rotator fitted, view from back


If im not in the shack I will be in my truck.

You can track my truck on APRS and see LIVE images from my webcam at copy and past or click


Tower work again.

I have put my X700 vertical back on the tower and need to guy it now. Over the next few weekends I will make the three ground fixings and get it sorted. I am amazed it never fell over with the beam on it last winter.


Click images for full size photo

fixing 1

1st of 3 anchor points, top of concrete post

fixing 2

2nd of 3 anchor points, 6ft into the ground

fixing 3

3rd of 3 anchor points, on side of garage with T&K brackets

rotator cage

The 3 Guy lines fitted to rotator cage "also 80m wire to the right"

tower & beam

Finished job, seems much more stable :-) also not twisting so much now.

Tower & antennas

Full view from back of QTH. KT34A with a X700 vertical on top


KLM-KT34A now finished :-)

Frequencies of operation:
14.0-14.350 MHz
Gain: 7 dBd +/- .3 dB across each band
F/S: 30 dB
F/B: 20 dB
Feed Imped: 50 ohms with balun supplied
Power rating: 5kW PEP
Boom: 16 ft. x 3 inch O.D.
Mast: for 2 inch O.D. (standard)
Element length: 24 ft. average
Turning radius: 16 ft.
Wind area: 6 sq. ft.
Wind survival: 100 MPH
Weight:45 lbs
Shipping size: 98" x 9" x 7"
Shipping Wt. 58 lbs.

KT34A spec
The KT34 A Elements

On top of the KT34A is my Comet H422V

Newly designed High Power (1kw) 4-Band trap dipole antenna, . Can be used both straight and /or V type. When used as V type, ready to transmit from low position of 3m high from the ground. A CBL-2000, high power 2k/SSB balun, is included as a standard accessory, this also helps prevent TVI, BCI, and other possible sources of interference. Specially developed high power trap coils assure high power QSO's constantly.

Comet H422
  • Frequencies : 7,14,21,28 Mhz
  • Impedance : 50 Ohm
  • VSWR : Less than 1:1.5 at centre frequency
  • Maximum input Power : 1Kw SSB
  • Connector : M Type ( SO239)
  • Maximum Wind Velocity : 35m/sec
  • Length : 10.3m straight assembly, 7.4m V type
  • Weight : 5.4Kgs
  • Rotation Radius : 5.3m Straight, 3.8m V Assembly
  • Suitable mast diameter : 38 - 62mm


Emotator Logo

I have moved the Emotator infomation to its own page

Click HERE

All built up and ready to go on the tower

An other view of the KT34Arotator cage

The KLM KT34A up at last

Well it is up but will be coming down next summer to have the M2 upgrade fitted as it arrived too late to fit this year.

Alpha ETO Power

Visits to the SSTV site today
Rate this site

(with 10 = top)

QRZ Ham Callsign lookup

free counters

SSTV_ATV Webring

The SSTV & ATV Ham WebRing
| Next | Previous | Random | List | Home/Join
SSTV_ATV Webring

Page Layout � G0HWC

Verified site 100%