GM4KGK

Radio - HF

Some of the equipment currently in use at my station

Main interests are CW and Digi-modes

Home Up 1980's & 1990's 2000 & Later KW1000  

 

 

 

 

 

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Kenwood TS890

Purchased (new) in May 2020. Introduced in 2018 it competes with other mid/high end rigs like the Icom IC7610 and the Yaesu FTdx101 both of which were assessed before making making a decision as to which of the three best suited my purposes.

Having used the Elecraft K3 for 12 years I never felt the need for a second receiver which made comparison slightly easier. Another factor which influenced my choice was the hybrid architecture that combines SDR technology with the use of a selection of crystal filters rather than relying entirely on DSP to determine filter characteristics - again similar to the K3. As standard the TS890 comes with four crystal filters, 15kHz, 6kHz, 2.7kHz and 500Hz to which I have added the optional 270Hz narrow CW filter.

There is quite a learning curve with a relatively complicated rig like this and frequent reference to the manual is essential to tailor the various features to ones operating preferences. For me that is mostly CW with some digital modes when things are quiet at the lower end of the bands. Even after some months of operation I'm not sure that I'm getting the best out of the rig. For SSB afficionados, be aware that no microphone is supplied with the radio.

 

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Icom IC7400

This radio is a later version of the IC-746 which I had used in the past (marketed as the IC-746 Pro in certain parts of the world). I was curious to see how it compared with its predecessor, to be honest I think I preferred the original. Total reliance on DSP for filtering just doesn't feel right to me. Nevertheless it is a good rig and having 100  watts of RF available on 2m is a big bonus if you are a VHF operator. I don't often stray above 6m!

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Elecraft KPA500 Linear Amp

This compact 500 watt amplifier fits into the same size case as the K3 transceiver and covers 160 to 6m. The output stages are run from a linear 70 volt supply which utilises a large toroidal transformer. A switched mode supply would have been the obvious choice for a small cabinet, but the linear supply eliminates any possibility of RF hash. 

With a suitable interconnecting cable the amp would follow the K3 band switching and once a few parameters had been set up the K3 effectively became a 500 watt transceiver. I believe similar interfacing can be achieved with the TS890 but I have not yet implemented that facility. A tap on the morse key invokes RF sensing and switches to the appropriate band.

Two rows of LED's indicate power output and SWR. The orange LCD displays various parameters, voltage, current, temperature, power, SWR etc.

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KAT500 Auto Antenna Tuner 

My latest acquisition from Elecraft. Rated at 500 watts with SWR up to 10:1 and a kilowatt if the SWR is less than 3:1. It certainly matches my 42m random wire without complaint on all HF bands from 160m upwards.

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Elecraft K2 100w Transceiver

Very compact 100w transceiver purchased second hand in 2016. Needed some alignment, particularly the filter set-up. Of the many options available for this rig only the 100w PA, SSB and 160m modules have been fitted. Works well, I like the built-in keyer for CW. Its small size makes it a useful companion on our travels.

Vibroplex twin paddle morse key. This generates the dits and dahs that make up the Morse code (CW). Most people seem to opt for the Bencher paddle but I have always preferred the more solid feel of the Vibroplex. 

Keyer is home brew built round the K1EL PIC design. Speed variable from 10-50 wpm. Now mostly redundant as I use the excellent internal keyer found in nearly all modern rigs, but should be useful for driving the IC7400 which only offers the option of Iambic Mode 'B'. I started out with Mode 'A' and I'm stuck with it.