Kenwood DG5 Emulator with Nixies is working!

I seem to be going backwards with my display technology for this emulator. First it was an LCD display, then LED’s, now Nixies! I completed wiring up a set of TaylorEdge SmartNixies ( using the IN-12b Nixie tube. They make using Nixies with a micro-controller easy. Each module has a PIC controller that is I2C addressable, so wiring is much easier than wiring up all the cathodes and anodes of 6 tubes – just +5V, +170V (for the tubes), GND, and SDA/SCL data lines. 5 wires daisy chained together.

I need to find an enclosure to get this mounted in, and given the size I’ll need I am thinking about a wooden enclosure with a speaker as well, unless I find some old test equipment shell I can mount this in – like an old Heathkit Frequency counter or similar.

So, to review, LCD is nice, LED’s are correct (the original DG5 used LED’s), and Nixies are the best!

DG5 Emulator boards SOLD OUT.

The last 10 orders or so came in very slowly, so I’ll have to wait and see before I order more. I am hoping with the improvements made to the code, and a 7-segment LED version working and (hopefully!) a Nixie version not far behind that there will be more interest moving forward. I’ll post more here as I make progress, I have some mechanical work to to on the 7-Segment version before I shoot a video and post it. I have the front panel cut and a bezel installed, and 3 discrete 3mm LEDs to indicate USB/LSB/CW done, just need to work on getting the display mounted in the case positioned behind the bezel properly.


DG5 update – switched to LED’s, and prepping for Nixies!

After a little over a year of selling boards, and a busy life with a new job, I finally had some time to do a few things I have been meaning to do for some time. I have always wrestled with what I released – the hardware seems pretty solid, but I never liked the code all that much, and the LCD display was actually added in version 1.1 – the original version only was for creating a computer interface for the TS-520. So, when I added the display I used what I had on hand – a 2×20 line LCD. It works, but lacks character. Actually, it displays characters just fine…

This past weekend I had some time to do several things – clean up the code so it’s more readable/serviceable, fork the code to a version with a MAX 7219 based LED display instead of the LCD display – more true to the original DG-5. I also added some averaging/smoothing code to help with display jitter (switching between 2 least significant digits), added correction factor if needed – more on that below, changed the gate timing so hopefully it is more accurate for most folks (again, see below).

But the real reason I got in there and cleaned things up is I am planing on interfacing some IN-12B type Nixie tubes. The original DG-5 was LED based, sure, but it at the time that LED’s were just supplanting Nixie tubes, so a Nixie display would be “right”, and totally cool and retro (just like the TS-520)! However, just about EVERYTHING out there running Nixie’s today is a clock, there is little beyond time keeping in the Nixie world today. I ordered 2 Nixie clocks to see what I can do to convert/adapt the hardware and software to a frequency display.

I have one of the clocks up and running, an it’s gorgeous. It’s from John Taylor’s shop Tayloredge in San Diego, he has IN-12B nixies on a I2C PCB – perfect for interfacing to a micro-controller! I have another, Arduino based Nixie clock on order and I’ll see about what way I want to go with this. If others are interested in a Nixie based DG-5, let me know.

Couple of observations after spending the weekend hacking. I built a DG-5 board to do testing on, and for initial tests I used a Arduino UNO clone at first, and wow, a ceramic resonator as a clock is TERRIBLE for a frequency counter project! Which is why I tell folks to get an Arduino Duemilanove – they use a real crystal. I observed a 3k dial error, and 1.8k of drift as it warmed up! The Duemilanove uses a +/-100 ppm crystal (as far as I can tell), which is still not all that great, but it works satisfactorily in this application. +/- 10ppm crystals that will fit on the Duemilanove are only $0.49 from Mouser – I might grab some next order and see about upgrading a Duemilanove – that should be way more than enough accuracy/stability for this application.

Anyway, I’ll post the code in a day or two – I managed to use the existing LCD headers to connect the LED display, pictures to come.

Edit – Video of the new code in action on the Max based LED display:

Edit – here are the new Arduino INO files. The new code has the improvements listed above, even on the LCD version that many folks have. Please load it on to your DG5 emulator and let me know what you think. Hoping to get the Nixie version done sometime soon!

LCD Version 1.6.2

LED Version 1.6.2


DG5 Emulator PCB stock getting low (and Happy New Year!)

As of 12/31/15 (just 2.5 hours before 2016 in fact) there are 8 boards left in stock. Sometimes it takes me a few days to get to shipping, but with family/work I can’t always be as quick to get them out as I’d like to. Thanks for the continued e-mails and posts about your projects, glad to hear about folks building and using the boards. Happy New Year!


New run of DG5 Emulator PCB’s has arrived!

I received a new batch of the DG5 emulator boards this morning, made by the same US manufacturer. I also was able to lower the price from $10 to $8. To order a board, please go to the project page – and read thru the project to see what you’re getting yourself into! There is a PayPal “Buy Now” button at the end of the project description that will take you to the PayPal site for order processing.

Thank you everyone for your continued interest!


New order of PCB’s for the DG5 emulator has been placed

Based on the feedback and e-mails requesting a DG5 emulator board, I placed an order for another run of PC boards – should ship on the 11th from the PCB house here in the US. I’ll post here when the new boards arrive and are ready for shipment, and I’ll do my best to individually e-mail those who have written me over the past few months.

Thanks for your continued interest!


DG5 boards SOLD OUT.

I am out of the DG5 emulator boards. Given that the last few boards came in slowly, I am not planning on another board production run at this point. If enough folks want one (make a post below), I’ll look into another run of boards. Thanks to all who have purchased, and I hope you’re enjoying your Arduino AD5 emulator!

7/31/15 – I have received a lot of interest over the past few months, so I have put in a request for pricing on another order of boards – will let folks now if I pull the trigger! Thanks for your patience!


DG5 Emulator boards still available as of 2/8/15

DG5 Emulator boards are still available, 10 left as of this morning (2/8/15). Details on the project, with a link for ordering a board can be found here.

It sometimes takes me a day or two to respond to e-mails or posts made as I have a new job that’s keeping me busy. I took a position back in November managing a public safety radio system, an 800Mhz, P25 based trunked system with about 133 repeaters across 13 sites! There’s a lot going on, so I haven’t had a whole lot of time to play around with the TS-520S and the DG-5 emulator, however, one of the points to the open source movement is to allow for others to take a project and run with it. I had some code on the running on the Arduino late last year along with a AD9850 DDS board that added a DDS VFO to the 520S – there’s lots that could be done if someone want’s to put in the time!


UPDATE – as of 2/13 I only have 4 boards left. If there is continued interest once these are gone, I’ll make a 3rd run of them.

UPDATE – as of 2/15 I only have 2 boards left.

Digital readout for the original TS-520 by Mark Mohrmann, WA2FXM

Mark has written up a terrific document detailing how he added the Digital Display to his non “S”  TS-520.  There was a kit for the TS-520 back in the day to add the CAR/VFO/HET signal outputs, the TS-520S came with this option built in. Mark details how he built the interface, including the buffer amp necessary for the HET signal.  Thanks Mark!