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Prototype Boards Arrived

The new DG5 emulator board (with Atmel 328p on board) arrived Saturday, and I put one together today. It looks good, the only issues were 2 caps were not labeled (silk-screened) on the board. Worked the first time.

Since there isn’t an Arduino board involved, there us no USB port to program the micro-controller. Instead, there is a FTDI header that allows you to plug in a USB to TTL converter – I am using one from Adafruit called the FTDI Friend. It includes a reset line wired to RTS, which allows the Arduino IDE to be able to program it. The board is wired to allow this to plug directly in for programming, other FTDI boards should work but might need a cross connecting wire to get the signals (TX/RX/GND/RESET) going to the right places. And the Atmel processor will need an Arduino bootloader for this to work anyway. There are a couple of ways to handle this.

  1. Buy (or use existing) Arduino with a socketed, 28pin Atmel 328p like the UNO to program the chip.
  2. Buy a pre-programmed 328p chip from me with either the LED, LCD, or NIXIE code pre-loaded.

If you already have an Arduino UNO or similar, you can program the chip, remove it and install it in this board. If you buy the chip from me, you don’t need an Arduino. You don’t need the FTDI board either, but you won’t be able to connect to it to enable debugging if necessary, or be able to update the code in the future.

Some pics:

The populated board, version 2.0.2
The new RCA triple ganged jack
With the FTDI adapter plugged in
Board attached to LED module

I corrected the missing silkscreen labels, and added a solderable pad to the 5V line on the FTDI header. You don’t want the 5V from the FTDI board mixing with the 5V on the board – the linear regulator provides nice, clean power, and when the 5V from the FTDI board was connected, the displayed frequency jumped around. As soon as I disconnected the 5V from the FTDI board, it wen’t back to smooth operation. The solderable pad will allow you to bring 5V to this pin – I will be trying a FTDI/Bluetooth board that will need power in the future.

I am thinking about kitting (include all parts except case/chassis) up a couple of these boards with the parts I have on hand, I’ll have to add up the costs and come up with a price. If there is a lot of interest in having it kitted, I’ll see what I can do. I am not trying to run a business here, and I don’t want to get sucked into a huge time waster, but this is a fun project and I am willing to make it a little easier to get off the ground. Let me know your thoughts in the comments!

Lastly, I have the one built prototype board, and have 2 more PCBs. I might build them, and put them on eBay to see what happens, no chassis, just the populated and working board as seen above. I’ll make a post here if I do!

The DG5 can be a Heathkit SB-650 emulator too!

Dave Johnson, WB4JTT has written up a document on how to use the DG5 emulator as a Heathkit SB-650 emulator! The Heathkit SB-650 is an external Nixie tube display, much like the Kenwood DG5. In fact, it uses the same 3 frequency scheme as the DG5.

You can download his detailed document here: USING THE KV6O DG-5 EMULATOR IN HEATHKIT EQUIPMENT.PDF

I have a SB-102 waiting to get on the bench, I’ll defiantly have to adapt it for use with the DG5/SB-650.

I have created a project page to track this offshoot – hopefully we’ll get some build pics!

New(er) DG5 Board Design

The prototypes I received had a few issues – I neglected to add filtering caps for the supply as the original design didn’t need it – the Arduino host board had them. I also had a couple of wiring errors. The bigger issue was the lack of availability of another part – the three RCA connectors. It turns out that SparkFun no longer has these parts, and when I checked with their supplier (4UCON) the minimum order was 3000 pieces. Not happening.

Version 2.0.2 has some corrections, and incorporates a triple RCA connector that is available from Mouser. The jacks are spread out a little further as well, which is probably a good thing as the original was pretty tight due to the limitations of the Arduino Shield size. The 2.0.2 version is a little wider as well as longer.

The board is now 3.5″ X 2.5″.

I’ll order another set of prototypes to test, and hopefully be able to make a larger order to make available. The existing shield based version still works just fine, you just need to source a Arduino Duemilanove (or equivalent), and solder coax jumpers to panel mount RCA’s as the PCB mount RCA’s the board is designed for are unavailable.

New schematic:

Download (PDF, 54KB)

Prototype PCB’s round 2 have been ordered from OSHPark, more to come!

New DG5 Board design

I am working on an updated design to the DG5. Rather than being a shield for an Arduino, this PCB has the Atmel 328P chip on the board, along with room for a proper crystal, reset switch, and FTDI programming header. The main reason for doing this is the preferred Arduino to use – the Duemilanove – is getting pretty hard to find as this was a 2009 model. The later boards all use a ceramic resonator as the clock for the chip – which isn’t nearly accurate or stable enough in the role of a frequency counter.

The input side of the board is unchanged, the Arduino Shield headers have been removed and some rearranging of IC4 & IC5 to better allow the addition of the Atmel 328P (what is used on the Arduino’s) and the supporting hardware.

There is no USB port on this board. It would best to still have an Arduino to be able to load the software, as the bootloader comes on the chip when you buy an Arduino. If you have a chip programmer, you can do this without an Arduino. Once the chip has an Arduino bootloader, you can program via the FTDI header – a TTL interface that works with something like this from Adafruit:

More to come, I just sent off for a set of prototype boards. There is no advantage upgrade if you already have the shield working – this is to address the lack of crystal controlled Arduinos moving forward if all goes well. This also means you’ll need to have a programmer or arduino anyway – and need one of these FTDI boards (above) that cost as much as an Arduino anyway.

Steve – KV6O

New run of DG5 emulator boards in stock

I received another run of 100 PCB’s for the DG5 emulator, project info here.  Please read before ordering – this isn’t a kit – you will need additional components.

INTERNATIONAL BUYERS PLEASE NOTE!  Please e-mail me at (mycall is the website you’re on!) before placing an order.  On January 21, 2018, USPS stopped allowing USPS First Class Mail to contain goods, only documents.  Rates for goods are MUCH higher, unfortunately.

ALSO NOTE (2/8/2020): The Arduino Duemilanove is difficult to find, and the 3 RCA connectors used in this design are no longer available. If you have a Duemilanove, and can solder jumpers to panel mount RCA connectors, you should have no problems.


New DG5 PCB batch ordered

UPDATE 10/17/19 – new boards have arrived, hopefully I can get the ordering process up and running this weekend.

I have ordered another 100 boards, which should be here in a few weeks. There still seems to be interest, so I’ll keep supplying the boards! I’ll post an update when they are ready to ship.

International shipping costs skyrocket!

I don’t know what the USPS is thinking, but I can no longer ship international for the $2.50 I have been charging.  The USPS rate for a document is about $2.50 (for 1 ounce), but for goods it varies – I tried to ship to Australia and it was over $13!  Bottom line, if you want me to ship internationally, please send me an e-mail first with you address – I’ll have to see if Paypal can do the calculations, but in the mean time please ask first at my call @ my (same as the website you’re on!)

New boards in stock!

I received another run of 100 PCB’s for the DG5 emulator, project info here.  Please read before ordering – this isn’t a kit – you will need additional components.

Same price, $8.00 + $2.50 shipping for as many boards as you like. In most circumstances, I can ship internationally for this price as well. Rather than having to find the link to order on the project page (which has gotten rather large!) you can use the link below:


Another 100 PCB’s ordered!

UPDATE 7/6/17 – The last 2 boards shipped today, so I am officially out of stock for now, but more are on their way.

I placed another order for 100 PCB’s with the same PCB house that made the last batch, should be here in a week or two.  In the meantime, I am selling the remaining few boards I have to folks who have written me wanting a board.  I *think* that means ~180 boards shipped so far, I’ll have to look at my previous orders.  I hope folks are having fun with the project!