INRAD RX7300 & retain ATU

Having seen the video on splitting the audio source from the main antenna and using a secondary ‘receive only’ antenna for the MFJ-1028 I thought this was an excelllent idea to deal with the QRM I have.

IC-7300 and RX7300 – no ATU tho

This video gives an excellent example of how to install the RX7300 and all the necessary connections. However, I use an MFJ-993B on 160m although my end-fed antenna is only designed to goto 80m. The internal ATU is good upto SWR of 3.0 approx, so an external ATU becomes essential.

My first ‘issue’ was getting the case off. I read comments that others had suffered this as well, beit from overight screws, or using the wrong screwdriver. I found a screwdriver that worked perfectly, but one screw (speaker screw, top left from the rfront) wouldn’t budge. In the end i relcutantly used a dremel and a small drill bit to remove the screw.

I do not understand why manufactures put screws in so tight. I wasnt happy about using a dremel on such a new piece of equipment.

I looked at the ATU cable and where it could fit. I wasn’t going to cut the case, thats for sure, and whilst i dont use the other sockets at the moment, i may do in the future. It felt like i was gaining one feature, i.e. to tap the RX circuit but had to lose another. The Instructions for the tap kit specify that the ATU cable be tucked away and kept away from the fan. However, this gave me an idea to look at could I route the cable around the fan enclouser and not-tighten the screws quite so much ?

I carefully fed the ATU wiring around the fan enclousre, not thru it, but between the fan case and the chasiss of the transceiver. I put on electrical tape onto the wire and the chassis to provide a degree of protection to the cable.

I was able to get te ATU cable and the RX Tap out of the casing nicely. The next step was to do some basic testing of the transcevier, firstly without the ATU to ensure receive was working correctly, then to test some low-wattage (WSPR) and then higher (FT8) transmissions.

I was able to receive WSPR no problem and also transmit and see my transmissions were being received via map. This was on 1W of power. I then proceeded to FT8 on 40m, as this is a popular frequency any time of day with generally good propergation. With 20W I was quickly able to make contacts and confirm my RX tap was working correctly and my TX was working correctly.

I attached the external ATU via the power and re-routed the antenna feeds to go via the ATU. I kept the RX tap still in a close loop to ensure my previous setup was working correctly.

I was pleased to see that I was reaching Europe on 80m and low SWR, so the transceiver was working well.

I will monitor the fan on the IC-7300 to ensure the the wire between the PCB and the ATU are not being ‘clipped’ or any other damage. Next step is to fit my receive only antenna and test the phasing/nulling of the MFJ-1026.

Until next time, 73.


Been busy !

So apologies for the lack of posts – having passed my Intermediate, I then found myself with quite alot of work/other commitments, but heres a condensed update – i’ll do a lengthier one on each topic at a future date.


Up until recently I have been using a vertical di-pole, namely the DX Commander multibander. Whilst I’m happy with how good this antenna is, part of the hobby is learning and trying out new things ! After reading several very promising reports, I ordered the UK Antennas multiband end fed antenna. This product does deserve a write up of its own, which I will do in due course.

Needless to say, I am amazed at how well this antenna performs. It requires quite an extensive amount of space and I was able to re-use my DX-Commander masts as supports. I had ordered and tried to use Sotabeams, but for extended operation, they just didnt seem as stable and well built as the DX Commander. Good news is that I’ve ordered a DX Commander SOTA edition – looking forward to building and trying that out. The Sotabeams will probably stay in storage until i can go out /P /M and use them as ‘temporary’ mobile antennas.

Weather Sats

Having built and used my own ‘V’ dipole for NOAA and METEOR and was really happy with the results, i went to the next level and ordered a helical antenna for improved reception.

This came from the US and I think is hand built to order by National Antenna Whilst I could build a DIY version, I’m averse to going to large shops unless its essential at the moment, the reviews of this antenna are fantastic.

I setup the antenna and started on my mac to start with, and was impressed with the results, as this is somewhat manual and labour intensive, i then setup a raspberry pi running raspberry-noaa Whilst I looked and tried other installations, this was by the far the simplests and easiest to setup. The combination of an amazing antenna and good programming produced frankly astounding results, including my first ever METEOR-M2 decode – all full automated !

First HF QSOs with 2E – new Digital and Telephony

I was very happy to make a QSO with G7VRD. Having metup via the reddit talkgroup and being ‘local’ in terms of radio, we had never been able to reach each other. With the new installation of the end-fed, I was able to make contact on 80m via firstly WSPR then we tried out a variety of different modes. G7VRD was really great in helping me thru and testing various types, having varying degrees of successes across them.

I was also able to make contacts for the first time via Telephony. I had a great QSO wtih G8MNY who gave me a very detailed signal report, including play back of how i sounded, which was really useful. The combination of end-fed and additonal power is really helping me more on HF.

Whats Next ?

So i have a couple of other immediate things I want to do and are in progress, probably the most important is getting a receive-only antenna setup to restore use of my MFJ-1026 which performed really well previously.

Here is the video from youtube which shows what I’m aiming for – with VDSL in the UK i’m hoping this will help eliminate the QRM in my urban setting.

excellent example of noise cancelling with IC-7300 and MFJ-1026

Now i can also run a beacon, i want to get my PI-WSPR station going on 40m, so will see if i can get the 40m inverted v dipole up !

Until next time (which will be sooner !) take care, stay safe and 73 !

40m propagation / Kanga Kit / Intermediate Exam news !

Its been a lovely warm weekend down in Dorset, and that seems to have affected the propagation. I had a great time on FT8 and JS8 Call, reaching amazing distances and really good signals being put out and received. I had many logged contacts and good signal reports.

40m got *busy*

By the evening 40M got as busy as I have *ever* seen it, as shown in the picture above i switched about the bands and was making contacts on 15M as well, it was the best conditions I had seen so far !

Resume work on the Kanga Kit !

After a break of sometime, I have resumed work on my Kanga Kit – this fits in with the news I’m putting below, but I have a big thanks to John Clements who helped me fix a fault with the kit I was unable to locate. John found the issue (soldered pin-header together – hidden by the plastic) and returned the now working Kanga kit to me ! I have resumed work and am taking my time – I’ve completed more work on the resistors and capacitors on the Active BPF.

kanga kit with added capacitors for BPF stage

I’m taking my time, esp as the board is now quite ‘busy’ – the next step is to add diodes and IC’s. Its really close to completing the build, but taking my time to ensure no more mistakes !

RSGB Announce Intermediate Exams on-line !

As shown in the picture above from the RSGB site Intermediate exams will be available from the 13th ! (in 8 minutes time as of writing) i’m very excited that i will be able to book my exam and get use more wattage but also gain more insight to a very interesting hobby as I continue my amateur radio development.

Whilst the practial assessment is waived currently, i will continue to build my Kanga Kit, so if the issue did come up of what Kit I did build, this is well recorded and documented.

To close the evening off I had a splendid evening enjoying the good propergation and just listening to the QSO’s on 40m. The ICOM’s filter and noise blanker are amazing, SSB has never sounded so good.

The waterfall is incredibly useful for visualising contacts

What i really like about the 7300 is the ability to visualize all or in very close range the frequency. I can easily find conversations happening and enjoy what is being talked about and the signal reports. Almost everyone i hear on 40m is using 100W but the distances are still several hundreds of miles – in particular hearing about life on Guernsey was very interesting – seems they are Covid free and back to some ‘normality’.

Well, heres waiting on being able to book my Intermediate Exam and enjoy more contacts around the world !

  • UPDATE – Have booked Intermediate exam today (13 June) for in August for more time to do a structured revision plan and passing !
  • Am still planning to finish my Kanga Kit ! making daily progress !

73 / Alan / M7ALU

Its all change at the QTH !

So I’ve had a very busy week or two both on day-to-day 9-5 (+!) and around the shack.

I am lucky enough that I get a gardener once a month to do all the lawns and bushes, and I used the opportunity this time to take down all the antennas allowing for a very good tidy lawn.

DX Commander #1 in place, very well guyed down due to the wind we are having of late

I also wanted to try out a method of increasing gain and reception using a 2 Element Parasitic Array on the 40m band – the youtube video here is really good at explaning how the setup works. I was already lucky enough to have another DX Commander on order before Calum goes on his holiday, so I set about measuring the distances and getting the 2nd DX Commander setup for just 40m

The main difference between a parasitic array is that its just for a single band and the distance between the two is 1/4 wavelength, in this case 10m. The wire *should* be a little lower on the 40m frequency than the ‘driven’ – but I am going to double check that when it comes to more fetteling (cant ever get an antenna too perfect imho !).

As you can see in the pictures, I have followed Calum’s advice pretty much and put the radials down, doesnt matter on the 360, but the length is there for 40m. The main difference is that the radials are directly connected to the driven element plate and there is no physical wired connection between the two antennas. I did check the S.W.R. on 40m (and 15) and it was a more than acceptable 1.4:1 across the band *before* moving the radials up. (Note will be finding a cover for the SO239!)

I need to find a ‘good’ way on proving the parasitic is having the desired effect. Out of interest i did attach my rig master to it whilst transmitting WSPR on 40m and sure enough the SWR did go up, which does at least prove that its resonating a transmission on the right frequency.

In practice I gave trusty FT8 a go, and sure enough I was getting far more +db on the map than i have ever had. Now this isnt particuarly good ‘science’ as there could be so many reasons why that was happening, so i could of got lucky. But I will find (and if someone wants to add a comment please do !) on how to test the effectiveness (i’m expecting something like +3-5db gain) I’d be glad to accept it !

I have also upgraded my ‘main’ tranceiver, the reasons are multiple, but mostly the Icom 7300 got very good reviews and the price/performance balance looked amazing.

The Icom 7300 now in the shack

That is not to say that all the hard work and effort put into the Kenwood TS690-S will be wasted, absolutely not ! I have actually made another addition from Japan, this lovely microphone unit !

This pristine MC-85 came from Japan, sadly without box, but its immaculate !

I am hoping i can use the output switch between the Kenwood and Icom as this looks such a gorgeous microphone and the reviews of it are very promising.

I am going to put an end-fed multi bander on the TS-690S and having seen UK Antennas posted on the DX Commander Discord, done some research and went for it !

I have yet to install the antenna as I have moved my 2m/70cm mast to the rear garden. Putting out a big thanks to the after-sales support from Moonraker as I wanted to fully extended my 40ft antenna so i can use the 30m point as a ‘fulcrum’ for the end-fed antenna, creating a nice inverted ‘V’ to use.

Here is the mast I bought from them – the TMF-2 – it really is an amazing mast, yout get what you pay for with this. I looked at several sites, including this one on how to guy a mast. For 40ft it seemed i would need more guys – but gave the chaps at Moonraker a call to explain my mast, antenna and use, and re-located my guy-ring to a centre point on the sectional mast would be ok for a temporary antenna, with the obvious warnings for wind,etc.

I set about with my son (always good to have some help!) with getting the mast up and really well guyed in. I’m made up with the results, I’ve never seen the antenna looking so good and secure. The heavy duty base will be getting some additional ground-pegs but trust me that thing is HEAVY, its not going anywhere 🙂

40m mast with 2m/70cm J pole on top

I was able to reach all the local repeaters as before, but have yet to get a contact to check my signal report (such is VHF during the day time).

So there has been alot of change in the shack, but i’m really happy with the direction its going in !