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Yet Another FT-847

February 18, 2015, 4:04 am
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Well,

I came across another FT-847 recently; I was told it had the full 4M modifications completed. However I can see the old daughter board installed and not the pre-amp I would expect:


This was where I did an 847 mod a while ago and the pre-amp I expected to see:

http://g0mgx.blogspot.co.uk/2012/06/ft-847-pre-amp-installation.html

There is, however, this additional board installed either side of L308<<something>> where the something is obscured by the cables. You can see the board in the photo above - it's got G086C written on it. Any ideas what this is? This is the RF connections from the board:


There also seems to be a cable disconnected to the front panel:


Also I can see what looks like a voltage regulator in the middle of this photo here:



The power out is also lower than I would expect on 4M, perhaps the PA hasn't been modified correctly:

http://g0mgx.blogspot.co.uk/2012/06/ft-847-pre-amp-installation.html

Strange, egh?
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The Wall of Obsession

February 22, 2015, 3:28 am
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Well,

Please may I present the "wall of obsession".

Local conditions include a FT-DX-5000 I came across yesterday. Now I personally think my setup has reached ultimate status for what I want to do.

I am delighted.



You have to imagine that these three are up to no good; agree?


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The Yaesu SCU-17

February 23, 2015, 6:33 am
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Well,

I've been to see my chums at LAM Communications today and I brought home one of these:


It's a Yaesu SCU-17 radio interface unit. I've owned a lot of radios in my time, the most "modern" perhaps being the Kenwood TS-990 and the Yeasu FT-3000. Both these radios have USB ports on the rear and built in sound cards. You connect the USB port to a PC and low and indeed behold, you have an audio device to send Audio to and receive Audio from the Radio, you also have a "Virtual" COM port that you can use for CAT control. The other really neat feature of the FT-DX3000 that I believe is unique to that radio, is that you also get a second "virtual" COM port that you can use to control PTT, FSK & CW switching from PC applications. The 990 doesn't have this second virtual port and hence you still need a simple interface between the radio and the PC if you want to hard control the PTT line, run FSK RTTY or use an external CW keyboard.

This interface from Yaesu kind of gives you a half way house. I have two "virtual" COM ports, one for CAT control and the second for PTT & FSK - but unfortunately no CW keying so I've had to construct another simple interface to do that on the new FT-DX5000 I have:


It seems a real shame to me that I need to build an external one transistor switch to use a CW keyboard with a very expensive radio! If anyone knows different to me then please let me know. The 990 I have has two of those circuits (actually opto isolated equivalents) for CW and FSK keying.

Th Yaesu SCU-17 also connects to the Packet and RTTY rear connectors on the 5000 and takes care of AFSK audio interfacing as well as the FSK switching and CAT control.

I had some difficulty getting the COM ports to be recognised by the Logger32 software that I use here; I ended up swapping some ports about and assigning the SCU-17 ports a number under 10. Once I had done that all seemed to be well.

Good, egh?
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DSTAR - D what?

March 3, 2015, 9:46 am
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Well,

Not being one for newfangled technollogy, I've done no experiments whatsoever with the DSTAR capability in my IC-7100..... until now....

I wondered if I could hear the not so far away repeater GB3IN in Matlock, Derbyshire. It's a DSTAR note. I listened on an analogue radio and found regular bursts of what sounded very much like data.

This is GB3IN:

http://www.gb3in.co.uk/

I started by reading the IC-7100 manual, that didn't help much at all, then I found this video on You-Tube which is most excellent:


Good job Julien, N3FJ!

I was also sent an idiots guide which I have made available on the interweb here:

Idiots Guide

These two resources explained a whole pile of stuff to me. Here's the radio configuration for local CQ through GB3IN:


And this repeater configuration includes the Gateway callsign information for making Gateway CQ calls.



I'm still very much new to this and haven't figured all things out yet, but the pieces are slowly falling into place.

One of the accessories available for the IC-7100 is an external GPS - there is a 2.5mm jack socket on the back for connecting the receiver.

Now, a while back I did some fiddling with GPS receivers when I made the GPS disciplined frequency reference for the shack:

http://g0mgx.blogspot.co.uk/2013/11/gps-disciplined-really.html

So I am thinking it should be easy to connect one of the GPS receivers I have here to the IC-7100. This is how I think it should work and what the actually thing looks like in reality:


I'll connect it all together tomorrow and report back on what happens.

Dogs looking confused; my mum thinks he is almost asking if he should wake up the cat?


Fun egh?
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DSTAR GPS Connections - Really?

March 4, 2015, 2:21 am
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Well,

You may recall last time I was musing about connecting a GPS receiver to my IC-7100 to complement the DSTAR mode.

http://g0mgx.blogspot.co.uk/2015/03/dstar-d-what.html

Anyhow, I tested the electronics I threw together and found my voltage regulator to be highly suspect so I threw it in the bin. I hadn't got any 7805 regulators, so I had to construct a 5V supply using a LM317 I had. There's a really handy calculator here:

http://www.reuk.co.uk/LM317-Voltage-Calculator.htm

And I soon concluded that a value of R1 =  330R and R2 = 1000R would give me a 5.04V regulated output.

I built the 5.0V regulator and coupled it up to the GPS receiver; a GPS antenna that has been sitting on the porch roof for some time was connected to the antenna socket and a scope to the data output line.

Here's what I saw:


Now, clearly I can't read or interpret this stream of pulses, but it certainly looks like a RS-232 type data output to me.

So, I decided to connect it to the radio and see what happens.

Guess what? Nill, zero, zip, nada.

Now, there are a few variables here that I have to fiddle with. Firstly the data jack on the back of the radio, what is the pin out? There's nothing in the manual to tell me. I assume the ring of the connector is the ground, so we have two options there. The TXD and RXD could be one of two ways round. Lets' try the two options....

Guess what? Nill, zero, zip, nada.

Additionally there is the baud rate of the GPS data - is it 4800 baud? 9600 baud? Again I am not too sure.

I think the best thing for me to do is to hook the GPS receiver up to an Arduino board and see what the data actually looks like before going any further.

So here is a very Basic Arduino Scetch to read a byte from the GPS receiver and write it out to the Serial Monitor:


And this is the output:


So, this confirms that the GPS receiver is spitting out GPS data at 4800 baud.

So now I think I need to focus on the connection to the radio. There is NOTHING in the manual at all to tell you what the pin out of the DATA1 connection on the radio rear panel is. Time for some research....

I dropped Icom UK an email asking about the connections to the DATA1 port and very quickly received this image from then by means of reply:



Now, the radio is definitely configured for an External GPS connection at 4800 baud.... but still Nill, zero, zip, nada.

More head scratching required me thinks....

***UPDATE***

It's just come to me in a flash! My GPS receiver output is TTL and the IC-7100 needs an RS232 input. I need to convert one to the other!

Earlier on today by some total coincidence, I stumbled across the TTL to RS-232 converter I made back here for the FT1000D:

http://g0mgx.blogspot.co.uk/2014/01/the-cat-is-back-in-bag.html

Not that finding this made me think that this could be the problem here! Anyhow, I've hooked the board from that project to the output of my GPS:


And this is the input and output of the converter on the 'scope:


And low, and indeed behold, this is the output connected to the IC-7100:


It works!

Local conditions.

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Meteor Scatter with the TS-990 - Are you sure?

March 5, 2015, 1:06 am
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Well,

Fiddling around in the shack this morning and I thought I would share with you a video of the TS-990 being used in conjunction with Gemini 4 linear for Meteor Scatter in JT6M mode.


Local conditions.
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TS-990 on 2M 144MHz - no way!

March 5, 2015, 1:10 am
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My SWRs got no nose - How does it smell?

March 10, 2015, 8:13 am
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Well,

You may recall the 6 Element LFA 2M Yagi I installed back here:

http://g0mgx.blogspot.co.uk/2014/08/this-is-even-more-bonkers-than-before.html

plus the masthead amplifier I built and installed back here:

http://g0mgx.blogspot.co.uk/2014/12/how-can-something-so-simple-be-so-tricky.html

There has been something very strange indeed going on with this antenna. Here's the evidence as I see it:


  • The SWR varies - not while in use, but sometimes it's not as good as it was when I left it!
  • It is either good or bad, I have never seen it go from good to bad while in use;
  • When it's bad the Gemini linear trips with high SWR (which is good)
  • The bad SWR does seem to be more present when it's cold
  • When it's bad the SWR seems to be about 1.8:1
  • Having had the antennas down many times to look at this problem, the only thing I am suspicious of is a "back to back" N-Type connector that's up in the air. Everything else seems OK to me.
When I installed the pre-amp, I didn't want to hard wire it in so it was a permanent installation - I therefore decided to hard wire it to the cable tail that connects to the antenna, and fit an N-Type connector to the other lead from the pre-amp. This other lead is connected to the Westflex 103 that feeds back to the shack by means of a "back to back" N-Type plus the N-Type fitted to the end of the Westflex - got it?

So - the connectors are all expensive (not that this means they are good quality, but they look good to me) and they are compression fittings. No amount of wiggling these connectors will make the SWR change. 

I have concluded that the only thing that might be causing my problem is the back to back N-Type connector. To remedy this I have purchased a Female N-Type in-line connector which I can fit to the end of the pre-amp tail, thus eliminating the need for the back to back connector. 

Today I brought the  antennas down and found that by adjusting the 2M antenna, I could reduce the SWR further than it was when I started. Now, due to my suspicions, this was the return loss trace from the 2M beam last time I finished fiddling with it:


So, according to this I had an SWR of 1.55:1 last time I finished with the antenna, after my fiddling today, today my AA-170 analyser is saying this:



which is a return loss of 22.68 dB and an SWR of 1.16:1. My return loss bridge on the spectrum analyser is saying this:


which is that the return loss is 22.12dB and an SWR of 1.17:1 - which is pretty damn close to the analyser or perhaps the AA-170 is close to the SA. What I am trying to say is that the results are astonishingly similar!!

This suggests that I hadn't adjusted the antenna properly when I finished with it last time - perhaps I just got bored? Who knows!

I haven't fitted the female N-Type and will wait and see what, if anything changes going forward. If I have any recurrence of this jumping SWR the pre-amp will have to come down and the female N-Type connector fitted.

Odd, egh?  
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Transverting - Even More!

April 2, 2015, 12:08 am
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Well,

Following the success of my 2M transverter project back here:

http://g0mgx.blogspot.co.uk/2014/10/transverting-some-more-some-more.html

which I showed off working here:

http://g0mgx.blogspot.co.uk/2015/03/ts-990-on-2m-144mhz-no-way.html

I decided that I would like to have a bash at making one of these transverters for 4M. Sam, G4DDK agreed to supply me with a kit of parts for a 4M variant of the Anglian. There are about 40 or so component changes. This meant that the board needed the SMD soldering to complete the unit - the 2M version required no SMD soldering!

So here is the project in it's infancy:


And here with quite a few more components in place:


and here with it complete and in the tin screening box:


I've run all the basic tests and both the RX converter and TX converter are working fine. There is a 42MHz local oscillator (70 - 42 = 28) - as with the 2M variant, I have ordered a ZLPLL board from here:

http://zl2bkc.com/projects/zlpll/

to provide an external frequency reference to stabilise the on board LO.

I've started the PA board to go with the unit; it should deliver about 7W output.


I've decided that to avoid any switching between transverters I will leave the 2M box interfaced to the TS-990 and use this 4M variant with the FT-DX5000. That has a transverter output which is -10dBm rather than the 0dBm I require. I may have to experiment a little with the levels but I should be able to drive the 4M Gemini amplifier perfectly with this combination.

Let's see.

Freddy cat has been doing a fine job of being almost completely in the way throughout.


Local conditions.
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Transverting - Even More More!

April 2, 2015, 9:46 am
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So,

Following from the start of the 4M Transverter project I posted about last time:

http://g0mgx.blogspot.co.uk/2015/04/transverting-even-more.html

I've done some more today.

The power amp module is built and mounted on the rear of the enclosure with an aluminium heat spreader:


The rest of the enclosure is prepared:




The internal wiring is almost complete, I've just run out of SMA cables - which is a bit of a bummer! I'm also waiting for the ZLPLL from here to complete the project properly.

Not a bad start though, egh?
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Transverting - Complete!

April 8, 2015, 5:54 am
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Well,

The 4M Transverter I started back here:

http://g0mgx.blogspot.co.uk/2015/04/transverting-even-more.html

Is now **nearly** complete.I say nearly as I am still waiting for a ZLPLL board from here.

The interior has been completed and all wiring completed, here's a shot mid way though that process:


Now, you may remember that I have a Gemini 4M & 6M amplifier. Well, this was configured for a 25W drive level when I bought it, so I needed to modify it for the lower drive level of this transverter. The amplifier includes an attenuator which needed to be replaced. Here's a view of the Gemini with the covers removed:


In the photo above I have highlighted with a red circle the component that needed to be replaced. You can hopefully see that I have also had to remove the internal covers from the RF board screened enclosure to access the part.

Here's the RF board with the new attenuator installed:


This is working beautifully from the transverter now and giving me full power out from the transverter drive levels.

Good, egh?
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Transverting - Finished!

April 11, 2015, 7:08 am
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Well,

You may remember the 4M transverter I started making here:

http://g0mgx.blogspot.co.uk/2015/04/transverting-even-more.html

I mentioned that I was waiting for a zlpll from here:

http://zl2bkc.com/projects/zlpll/

to complete the project.

Well, it arrived today and I have installed it in the tranverter:


Marc, ON5VW was kind enough to offer me an on air test, so this is my signal as received in JO10 over the water in Belgium:



So that's the final proof of concept - all working as planed!

Good, egh?
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What's going on here then?

May 6, 2015, 11:41 am
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Well,

You may remember I've been dabbling with the WSJT modes using meteor scatter and you also might remember that I have a FT-DX5000 with a SCU-17 rig interface.



I tried using the 5000 for 6M MS the other day and found widely swinging power out during transmit. I've done some simple tests today on the set up and with the radio in TX and using a PC based signal generator I see this power output vs. audio frequency:


Now, I would expect this to be reasonably fat across the audio spectrum - this is far from my expectations! This clearly explains why, on TX in JT6M, the power out of the radio varies so much as the tones change.

It's not much better on RX when receiving noise on the band:

Again, I would expect this to be flat.

So, is there something strange going on in the radio itself in the audio circuits or is this the symptom of a spectacularly pants sound card in the SCU-17?

I wonder.....

More on this will follow.

** UPDATE **

I've drawn some conclusions here:

http://g0mgx.blogspot.co.uk/2015/05/whats-going-on-here-then-part-ii.html

Odd, egh?

Left a jumper on the desk today:


Local conditions....
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Whats going on here then - Part II

May 7, 2015, 7:19 am
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Well,

Following my musings about the really pants audio bandwidth from the Yaesu SCU-17 back here:

http://g0mgx.blogspot.co.uk/2015/05/whats-going-on-here-then.html

I've found an old external USB soundblaster soundcard thingamabob and hooked it up to my PC with the audio in and out directly to the PKT jack on the FT-DX5000 (the same connector the SCU-17 uses for audio to and from the radio).

Here's the comparison between the two:


So the old battered USB soundcard has a completely flat audio response, the SCU-17 is totally pants. I am rather horrified at the frequency response from this expensive Yaesu unit - I don't think it's even fit for purpose!

What  load of Dingos Kidneys.

Local conditions.
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The Tigertronics Signalink USB

May 9, 2015, 10:22 am
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Well,

Following my frustrations with the Yaesu SCU-17 rig interface back here:

http://g0mgx.blogspot.co.uk/2015/05/whats-going-on-here-then.html

and more here:

http://g0mgx.blogspot.co.uk/2015/05/whats-going-on-here-then-part-ii.html

I've been fiddling today with a Signalink USB interface. This suffers from similar issues to the Yaesu device, but there are a couple of excellent internet resources that help you fix it, here:

http://www.frenning.dk/OZ1PIF_HOMEPAGE/SignaLinkUSB-mods.html

and here:

http://www.k7sfn.com/projects/signalink.html

So here is my Signalink half way through the fiddling process:


One of the most important mods in the link above is the replacement of a cap on the board with a 33uF value component. My Signalink already had 33uF onboard so this was left as-is.

What I have done is (documented on the links above), firstly added a 4.7uF capacitor to the power rails for the internal PIC:


I have also removed the 1K resistor feeding the audio circuitry power and fed the supply via 470R and the orange jumper wire you can see. This takes the power from the PIC regulator rather than the dirty USB supply. I have also added 47uF tantalum capacitor to the USB power supply:


That has improved the audio response dramatically and here is what we see post modification:


Now, the Signalink doesn't include an FSK switch to run RTTY, so I have modified the rig -> Signalink cable to bring the FSK keying line to an unused pin on the DIL internal socket, and wired that through a 4N32 opto-isolator to a 9 pin D-type connector I have added to the unit:



This connector can now take a Serial-USB adapter so I can run FSK from the PC.

I've also sold my FT-DX5000 and bought an ICOM IC-9100. I have fitted the optional 3KHz roofing filter and the 23cm module in the radio:



Freddie Cat can't be comfy here, but has been supervising most of the day:


Local conditions.
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It's great to be in the fracas!

May 11, 2015, 12:08 pm
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Well,

Today has been an excellent day for 6M Sporadic E. This was earlier this morning:


And then tonight the band opened again:


If you haven't witnessed a Sporadic E opening on 6M before, here's a quick video of Tony, I2PJA received here in IO93GA (that's 715 miles as the RF flies):


I'm no 6M wizzo but here's my 6M QSOs from my log converted into a map:


Good, egh?

Local conditions.
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They call it the Magic Band....

May 14, 2015, 6:01 am
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Well,

Been messing about today on 6M. There have been quite a few openings over the past few days due to Sporadic E. This was the sporatic e cloud map from DX Maps earlier today:


The numbers in the boxes represent the MUF (Maximum Usable Frequency). This is the resultant QSO map:


How did I do? I worked a lot of stations in and around Europe, my best being 5B4AAB (Cyprus) and 4X4DK (Israel); both contacts must have been multi-hop Es. You can see the spots for 4X4 and 5B4 on the map above. I was particularly delighted to work 4X4DK as G3OCA was calling him and I was the one that bust the pileup! Ken, as usual, had a spectacularly bad signal that was half a mile off frequency. I was unlucky enough to spend some time with 3OCA when I used to go to the Nunsfield House Amateur Radio Group - he is the most arrogant man I have ever met.

This is my all-time 6M log converted to a map:


I am a member of the UKSMG (UK Six Meter Group), and they run a summer marathon on 6M. Here's the log table (before anyone else uploaded today!):


The only thing that I can guarantee is that I won't stay second for long!

good fun, egh?

*** Update ***

Christian SWL in JN77sn has sent me an Audio file of my transmissions from earlier today, take a listen:

Audio File
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New Antenna Time

May 21, 2015, 1:33 am
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Well,

Following all the fun I have been enjoying on 4M, 6M and 2M using Meteor Scatter I decided to upgrade the antennas I have for those bands.

Here's the installation after completion:


Nut's egh? Both the 2M antenna and the combined 4/6M antenna are from InnovAntennas. The 2M antenna SWR is excellent through the whole band, as is the 6M antenna:


The 4M antenna is not so great (due to the proximity of all the other metal):


I've spoken to Justin at InnovAntennas and he has had me pulling elements with cable ties and also wrapping tin foil round elements and sending him plots. I am sure we will get it sorted!



Fun egh?
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Israel on 6M? No way!

May 29, 2015, 9:13 am
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Well,

Here's a quick video of 4X4DK as received at my QTH on 16th May 2015. He was stronger on 14th May when I worked him.



My QSO is already confirmed in LOTW.


Good, egh?
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New Anennamabob!

July 14, 2015, 11:05 pm
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Well,

Quite some time ago I was rummaging on the internet and I came across this site:

http://n6bt.com/

Now, particularly interesting to me was this antenna:

http://www.n6bt.com/n6bt-Q52-p1-1.htm

It's called a Q-52 and is basically a shortened, inductively loaded 2 element beam for 20, 15, 17, 12 & 10 meters.

I ordered one and yesterday it arrived.


The antenna came in 7 parts; 3 part boom plus each side of the elements telescoped into itself - the box was surprisingly small.

Each element (the driven element and the reflector) have a switch controlled relay box which alters the element inductance.


Then there is a central wire connection box which allows you to run a control cable back to the shack where you select the band required on a rotary control unit:


So here it is on the mast, I have removed the MA5BB that I have been using for a few years; this antenna has less visual impact and also less weight. The main reason for changing the antenna is that this will give me 2 elements on 17 and 12, the MA5B is just a rotary dipole on those bands.



Time will tell, but the concept is certainly interesting. The construction of the antenna looks excellent and building it was very simple indeed.

More to follow!

New cats Maggie and Luna are settling in nicely:


Local conditions,

Fn egh?
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