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Sunday, 2 December 2018

Yet more Nixies!

Well,

My TEAS (Test Equipment Acquisition Syndrome) condition seems to worsen; I have acquired another Nixie frequency counter from that great auction site.

I've fiddled around with it considerably to get the internal clock to stabilise - some bright spark, maybe even the designer, has stuck a block of polystyrene (Styrofoam) over the crystal to try and maintain some temperature stability - but alas its all over the shop.

So, I've basically hacked two holes into the back of the unit and added an external reference clock input - this can be supplied by my ever faithful shack frequency reference.

So this is the unit; albeit on its side:


And here the small modification I've made:


The circuit forces whatever signal is on the input to be +ve DC - I've built it dead bug style on the back of the input BNC socket:


This is where I was poking about to find the clock output:


Using some of my other ancient test gear acquired through my TEAS condition:


Here's the result:


Lovely Jubbly.

Thursday, 22 November 2018

A complete waste of time?

Well,

I decided it would be a good idea to buy this from eBay:


Its an old HP DVM and Frequency counter; with a glorious Nixie display.

Initial testing revealed some issues with the frequency counter part of the functionality which I traced to an IC that was basically a set of NOT gates, so I removed it and replaced it with a good old 7404:


So, now the frequency counter is working, but the digit in the image below shouldn't be a 4 but a 0:


It works when the digit is supposed to be displaying a 4, 5, 6, 7 or blank:


So the rules of BCD tell me that the line that represents "4" is always stuck LOW no matter what the actual signals tell it to do.

There's a bunch of logic in the system, but there's basically a 4-bit latch that seems to have appropriate signals coming into it for this digit, but the "4" line is just stuck low.

The part is labeled a HP  1820-0116, and I think it's one of these:


So I've ordered some - the "2" on the end of the display also seems to be a similar problem so more to investigate.

So, I removed the suspect chip and fitted a DIL socket in its place:


I then swapped the chip in the "option 001" which is also socketed and bingo:


Now, I will need to do the same to the "2" digit chip as that is also stuck with a line low. Having investigated further, the 7475 I mentioned above doesn't seem to be a direct replacement for the HP device - I suspect the logic is the same, but the pin out isn't. I think the HP device is like this:


So, to try one of these I will have to make an adapter board of some kind. But maybe.....

Is it normal to buy test gear, to fix the test gear you just bought on eBay? I could always find another one of these for "spares or repair" and get some bits from there.....

I think I've got a bad case of GAS. I'm told there is no hope or indeed cure.

Wednesday, 21 November 2018

Morse Proficiency

Well,

One of the challenges I set myself for 2018 was to re-learn CW.

I passed a 12 wpm Morse test in 1989 to obtain my current licence; I didn't use the mode since and as a consequence was completely clueless.

I used the FISTS audio course plus some great help from a number of individuals on-air, and here is the result:


I'm rather chuffed.

Sunday, 11 November 2018

WAE RTTY time!

Well,

I've been fiddling in the WAE RTTY test this weekend; only dabbling - nothing serious about my contesting.

Here's my log as a map:


I used the IC-7610 yesterday and the TS-890 today.

I run with Writelog and have the MMTTY and 2Tone decoders on screen, plus I have a monitor connected to the Rig and have my eyes on a third decoder provided by the radio.

Here is the IC7610 as I have it set up in RTTY mode.


And this is the Kenwood:



Sorry, Kenwood, but the spectrum scope is just useless when it is that small - I really don't like this about the TS-890. The Icom only displays the spectrum when in decode mode, but on the TS-890 you have the spectrum scope and the waterfall on screen - both too small to be of any real use.

They are both fantastic RTTY radios though, the filtering capabilities of both rigs is second to none.

Friday, 9 November 2018

TS-890 and IC-7610 Panadapter and Waterfall - side by side

Well,

There's been lots of discussion on the TS-890 vs. IC-7610. So I've done a quick video of them side by side. The settings on the waterfall and panadapter are all customisable so there are many changes from the "out of the box" settings, and the radios are configured how I like them (which may not be your choice).

Anyhow, the reference levels are the same and I've configured the settings to be as similar as I think I can:



And here is the output of the DVI connectors on the radios:




Here's a third video with some more detail:



What do you think?

Saturday, 3 November 2018

TS-890 - Max PO Feature

Well,

There's been a few posts recently about the "Max PO Feature" on the TS-890; I have been using this extensively since I got the radio so that it plays nicely with my linear.

Here is the result of pressing and holding the "Max-Po" soft key on my rig:


So, in this screen you can set the tune power and also the max power out on each band. If you look at the image above you can see that the power output in the very top centre is 11W and is Yellow. The yellow indicates that its been restricted by the Max-PO setting.

You also need to be aware of the setting of menu 6-04:



Now, the only confusion I can see (and it isnt intuitive at all!) is when you press the "Max-PO" soft key with just a short press, you would expect the feature to turn on and off. Well, almost; here's what the radio does when the power restriction is already ON and you press the soft key with one short press:


So, the radio is telling me that the "TX Power Limit is turned Off" BUT IT ISNT!

Only once you press the "OK" soft key at the bottom centre does the feature actually turn off, if you press escape to suppress the on-screen message, then the feature remains ON.

So, once you press "OK" then the soft key changes to:


So here the feature is Off and the soft yes "MAX_Po OFF" actually turns the feature ON with a single short press.

A bit confusing, but easy when you know how!

An excellent feature for people like me who need different drive levels for different bands due to amplifier oddities.

NOTE: The power output limits are DIFFERENT by different mode, so here we have limits for CW:


and here a DIFFERENT set for FSK:


They aren't all listed on the same screen at the same time, so that had me confused for a while too!

All good.

Friday, 2 November 2018

TS-890 (and TS-990) with WSJT-X

Well,

I've been asked if I can help out someone who can't get the TS-890 (or maybe TS-990) to work with WSJT-X; they are running Windows 10.

So here goes:

Download and install the driver from Kenwood from here:


It's the "Virtual COM Port Driver" we are after.

Download the software and install it BEFORE connecting the radio to the PC.

It comes as a ZIP file and (a little confusingly) you need to select the appropriate installer, assuming you have a 64bit version of Windows, then use "CP210xVCPInstaller_x64" - you need to double click on the file to run it.

Once the software has installed correctly, we can now connect a USB cable between the radio and the PC:

Now, Windows 10 is very good (or bad) at trying to do everything seamlessly and failing. So once you have connected the radio to the PC and the computer has finished emitting its various pings and bongs, the easiest way to check for a successfull connection is to open device manager. If you type "device manager" into the search box you should see the option to open it.

Here's mine after the radio has been connected, we have three new and exiting things! We have an Audio device called "USB Audio CODEC" and also two new COM ports. Note I have had to expand the Audio section and the Ports section to see these devices. By default working devices are not immediately visible - only their groupings.


So, now we can go and download WSJT-X from here. At the time of writting thats version 1.9.1 but it is updated frequently so you need to keep on top of the versions.

I've installed with the default selections - I didnt change anything in the installer except selecting for a desktop icon:



Once installation completes, the software will run and we need to make changes in the "setup screen" by pressing F2 or using menu File -> Settings.

Here's mine, in this screen we just need to add callsign and locator:


So now, lets configure the radio on the "Radio" tab of the setup window - and this is where it got a bit complicated. I couldn't get the radio and WSJT-X to talk, so I cheated. I installed OmniRig from here.

Once you have OmniRig installed you need to configure it like this:


Please NOTE that the COM port selected above (in my case COM 4) may not be the same as yours - you need to select the Standard port (details of how to identify the port in Win 10 are listed on page 1-5 of the TS-890 manual). It's probably easier to try both and see which one works!

You MUST also match the Baud Rate setting above with the setting in the Radio menu item 7 - 01 "Baud Rate (Virtual Standard COM Port):


Then in the WSJT-X setup window "Radio" tab, I have this configuration.


You then press the "Test CAT" button and it turns green when all is successful.

Finally, we need to configure the Audio tab of the WSJT-X settings to use the "USB Audio CODEC" we installed earlier.


Now, on WSJT modes (and all other AFSK modes) it's important to set the Audio levels correctly.

On receive we want the greed audio bar graph to be at about 30dB with no signals (i.e. just background noise) and we can adjust that in the radio using menu 07-08 "USB: Audio Output Level".

Now, the final setting is the modulation source for the radio. If you are configured to use the radio in USB mode (see WSJT setting option 'mode') and you are using the radio USB connection, then you press and hold the "DATA" button when in USB and set it like this:




This means that the audio when the radio is in USB mode and the PTT comes from the CAT control the audio is sourced from the USB soundcard and not the mic.

On TX we want to make sure we have NO ALC and we can adjust that using the menu 07-06 "USB: Audio Input Level".

It's also ESSENTIAL that you set your PC clock correctly for these modes, installing Dimension 4 for clock synchronisation would be a most excellent idea.

Happy WSJT-X ing.