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Archive for January, 2016

Repairs and operations…. M0CVO Radio Blog 24/01/2016

January 24, 2016 Leave a comment

This last week turned out to be an interesting one.  On the 18th (Monday) I was given an old defunct radio – an IC-245.  It is in fact a 2m multimode offering FM, USB and CW and was one of ICOM’s first CMOS controlled radios boasting two VFOs and PLL tuning.  It was also the US version giving me a full 4MHz from 144 – 148MHz.  It looked to be in reasonable condition for a 39 year old set (last made in 1976).  However, it didn’t work.  The screws holding the case together were missing and on opening up I noticed that some wires had been snipped – perhaps it had been an attempt at doing a mod to add LSB or similar that had gone wrong.  Anyway, I repaired the wires but still nothing.  I contacted ICOM UK Ltd and they sent me a new MOLEX type connector for the DC input – this was also missing which arrived the next day.  Tracing the line back from DC in I noted that a small diode was “fused” (well, burnt out).  I suppose the radio must have been connected up the wrong way round at some stage or fed with too high a voltage.  Anyway, I checked in my junk box and found a small signal diode to replace the one that was crisped and tried again.  Presto! we have power.  Unfortunately though, no audio.  Anyway, I plugged a headset in at the back and audio was produced here so the audio drivers were obviously functioning.  I checked the external speaker/headphone socket but this was functioning correctly and switching back on to internal when the headphones were removed so I then checked the internal speaker.  lo and behold one of the wires through the cone was broken.  Anyway, I replaced the speaker with another and audio was heard.  On TX a full 10W was transmitted and the TX audio could be heard in  a second radio so all fine.  So now I have both the FT-480R from Yaesu as a 2m multimode (30W) and an IC-245 from ICOM as a 2m Multimode (10W) but with the advantage of also covering the 146 – 148MHz portion of the band.

IMG_20160122_111129 Inside the IC-245 showing the FM board

IMG_20160122_111253 Inside the IC-245 underside showing the add on SSB board.

IMG_20160122_105740 replacement speaker IMG_20160121_140859Operational

So what else of my week? Well although I have been rather busy this week with work I have also found some time to get on the air and was lucky enough to find an opening on 15m yesterday that enabled me to get LZ1012SGM into the log and earn 10 points towards a diploma.  I also managed to get Z62FB (Kosovo), 3Z90LKK (Polish club celebrating 90 years and offering points towards diploma) and Z63MES (Kosovo).  This morning I noted that there was a CW contest so I gave away a few points to some Russian stations on 20m.

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M0CVO Update

January 17, 2016 Leave a comment

As we awaken to the first layer of snow for the winter and temperatures of –1C I switch on the FT-DX1200 to see what is happenning on the bands (too cold to do anything in the garden).  Plenty of CW activity on 40 and 20m this morning but all calling CQ TEST.  Upon checking I discover it to be the Hungarian DX Contest this covers both CW and SSB modes on all the popular HF bands.  Anyway, I set about and work seven (7) stations in the space of 20 minutes.

Meanwhile, K5P has been operating during the past week from Palmyra, a tiny island in the Oceania, NE of Australia.  Whilst they have been working using CW, RTTY and SSB I have not myself been able to work them.  No surprise there, I don’t have a beam atop a 200ft tower and I don’t use >1kW RF power, but I have heard them, only faintly but definately there.  Interestingly though, on the DX cluster it was interesting to read comments from those unable to hear them suggestign that it was a poorly operated DXpedition and they weren’t using propogation paths correctly.  Hey, they’re a long way off and the formula is simple – if you can’t hear them you can’t work them!  It is surprising how many stations read the details on a DX Cluster such as dxwatch.com and just sit on frequency calling with no hope of being heard or hearing the DX station if he/she replies to them. It’s all about operating practice and etiquette!

Talking of ettiquette, Z62FB was working a succession of stations on 20m yesterday – had quite a pile up too.  Anyway, I became the last station he worked before going QRT when a rather impolite operator started calling CQ TEST just below so our QSO was in snatches between fast (voice keyer type) contest calls. No objection to the contest operators but they should check for activity before jumping on a frequency. Most important part of radio operation is “Listen, Listen, Listen and then Listen some more”.

Enough moaning now – during a dream (or partial awakeness) an idea came to me for a whole new HF antenna.  As this will involve using a jigsaw to cut aluminium it will now have to wait until the weather gets warmer (outside work) but at least I managed to scribble it down on paper the next morning and start planning it out properly.  A project for the spring maybe – I shall update this within the blog when I move closer to completion.

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Radio and space……..

January 10, 2016 Leave a comment

It has been quite a busy week at M0CVO Towers with one thing and another.  Inbetween working (yes there has been quite a large amount of that to do as well) I have managed some interesting QSO’s using SSB, CW, PSK and JT65. 

I know they are not really DX contacts but I worked 2 special event stations on Saturday :– SP0BASR, which is the newly set up Amateur Emergency Communications Network in Poland, using CW on 20m and HF6AN, commemorating six Polish Nobel Prize winners on 20m USB. I was pleased to manage these two as it meant fighting through large European pile ups to do so.  The secret to getting through a pile up is to be patient, listen to what others are doing and work to the timing of the station of interest. Good operating in other words.

However, what must have been the most exiting moment of the week was tuning the 2m sets in to 145.800MHz and 145.200MHz FM on Friday morning and listening out for the contact between Tim Peake (GB1ISS) on the International Space Station and the Sandringham School children (GB1SAN).  14.200MHz was the uplink frequency used by GB1SAN (Earth Station) and 145.800MHz was the downlink used by GB1ISS (Space Station).  I was amazed to hear Tim with a strong s8 – s9 signal received using a 17ft X-510N colinear and a MT-270 dual band mobile the uplink frequency was programmed into my FT-480R and I used a 10ele Diamond yagi beaming SW. I only heard snatches from the school with muffled audio though.  All was fine until some idiots started calling CQ on both the uplink and downlink frequencies.  This, unfortunately demonstrates bad operating practices to any listeners and is not a good way of promoting the hobby.

I have also started building a 5/8 wave 145MHz vertical antenna but calculating the impedance needed at the base is proving to be a challenge. More on this another time.

Pixie_box_2 pixie in a box…..

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Into the new year–radio tales from M0CVO

Into the New Year 2016 and having completed the QRP 365 challenge I set myself for 2015 I once again picked up the microphone for my FT-DX1200 and worked a few stations on SSB.  I was pleased to work 4X6TT – Amed in Israel – but I did also need to increase my power to 250W to reach him through the massive European pile up.  Still it’s a new DXCC entity in the log. 

I was also pleased to hear some local(ish) activity on 2m FM, having a nice QSO with 2E0ENN.  He is a bit to the east of me at RAF Cranwell.  At least I know that the cheap and cheerful dual band mobile I purchased recently is actually working.

Moving on I decided to experiment with some 3D CAD software and design some radio related models.  So I now have dipole and doublet centres, a base for a VHF/UHF 5/8 wavelength vertical (just need to find time to build the vertical), some guy rings for portable or SOTA ops and a case for the 20m CW Pixie transceiver I built.  The 3D model for teh Pixie case can be freely downloaded for personal use from HERE – you will need a 3D printer or relevant software to make use of it though.

Pixie_box_1Pixie_box_2 The 3D printed Pixie Box.

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