When is an RS-232 port not an RS-232 port (ACOM 600S RS-232 Mod)

I have been attempting to get the remote power on capability of ACOM Director Plus working with the ACOM 600S however no matter what I tried I was unable to make it work. I tried swapping to a null modem cable and amazingly the remote power on worked perfectly, however I could no longer connect to the amp from the computer.

On closer inspection of the manual, it would appear that there is something unusual about the wiring for the RS-232 port

At first glance everything seems fine, however pins 2 & 3 (TxD and RxD) are wired to use a straight through RS-232 cable, but pins 6 & 8 (DSR and CTS used for remote power on) are wired to use a null modem cable. This means that for full control of the amp a custom cable must be used.

What peaked my interest is the fact that pins 4 & 7 are noted as Not Connected, these are the DTR and RTS lines and are what’s used to tell the amp to power on. In order for this to work they must be connected to pins 6 and 8. It occured to me that it should be possible to make a modification to the amp to enable it to support a regular straight through RS-232 cable.

To that end i’ve put together a mod which can be found over at ACOM 600S RS-232 RPON Mod which details how to do this. It’s only useful if you intend to use the RPON capability through the RS-232 port, however it will avoid the need for custom cables and is still backward compatible should a custom cable happen to be used in the future.



When a Null Modem Cable is not a Null Modem Cable

While working on the next update to ACOM Director Plus (yes, work is now continuing on it), I couldn’t figure out why my code to turn on the ACOM600S was not working. I’d previously put this down to the fact that I have an early model and perhaps this wasn’t implemented then. I resorted to using my scope to check that the DTR and RTS lines were in fact being activated properly which is when I discovered that my Null Modem cable i’d been using for years now is not in fact a proper Null Modem Cable.

A normal (proper) Null Modem cable has the following wiring, notice the crossover of the DTR & DSR pins and the RTS & CTS pins, these are used for the remote power on of the ACOM600S, ACOM1200S and ACOM2000A with the RPON Module.

However after checking the wiring on my (commercially purchased) Null Modem Cable, I found it is actually wired like this.

As pins 2 & 3 are crossed, it still works fine for normal serial communications (without handshaking obviously) however all other pins are straight through, so anything relying on the proper use of handshake signals will fail.

The moral of the story, if you have issues with remote power on of the ACOM600S, ACOM1200S or ACOM2000A (or anything else that makes use of any control pins), make sure your Null Modem cable is actually wired fully to the Null Modem standard and not a half baked cable like mine.


ACOM Director Classic (ACOM 2000A Only) Updates – 0.7.2 & 0.8.1

Following feedback from ACOM regarding the remote power on using the RPON module for the ACOM2000A, two new versions of ACOM Director have now been released.

Version 0.7.2 is now available for anyone who was previously using 0.7.1 and does not want to use the experimental 0.8.x releases

Version 0.8.1 is now available for anyone who was previously using 0.8.0

These contain the following changes

  • Renamed to ACOM Director Classic as this is now the legacy version
  • Increased the RTS+DTR impulse time from 3 seconds to 10 seconds when attempting to remote power on the ACOM2000A

The increased impulse length from 3 to 10 seconds for remote power on is due to the power on failing on many occasions because the 1000uF electrolytic capacitor in the RPON adapter input does not get charged to the required voltage level. The most likely reason for this is the more recent USB to RS232 converters not properly meeting the RS232 standards.

These versions can be downloaded from the following locations

0.7.2 Download

0.8.1 Download

With regards to ACOM Director Plus, work had stopped for a while due to some extremely time consuming work comittments, these should be coming to an end soon however they have prevented me from furthering the progress of this. They’ve also meant i’ve not been able to monitor my radio related email very often, so if I haven’t responded to you, my apologies, I should be in a position to catch up very soon.

Cabinets, 80m Antenna & Rig Changes

The last few weeks have seen some good progress on getting the new station built, the external cabinets have now been installed, these are Schneider Electric Spacial CRN cabinets and measure 600mm x 800mm x 300mm. From left to right they’ll be used for 240v Mains Electric, control equipment (more on this in a future posting) and RF Switching. These are great cabinets as they’re relativly inexpensive and are IP66 rated so provide good weather proofing for the equipment. My location is very exposed to the weather so this is an important consideration.

With CQWW SSB coming up I wanted to be able to get on 80m, so figured it was time to convert the DX Commander into an 80m capable antenna. The 17m element was removed and replaced with an 80m inverted L element, with hindsight I should probably have removed the 30m element but i’ll address this once I move the DX Commander to it’s permanent location. The end of the inverted L is supported from a Clansman 5.4m Mast i’ve had laying around for years. The 80m performance seems to be pretty good and will certainly do as a temporary solution for 80m.

Finally, and perhaps the most exciting change is the new HF rig, i’ve had my trusty Yaesu FT-2000 for a very long time and the opportunity came up for me to acquire a Kenwood TS-990S. The descision was a very easy one so the FT-2000 had to go. I’ve only had the TS-990S for a short time but so far i’m very pleased with it. The performance is considerably better than the FT-2000 and it’s a fantastic rig to operate. I’m very much looking forward to putting it through it’s paces in CQWW SSB.

ACOM Director Plus 0.6.0 (beta)

ACOM Director Plus 0.6.0 (beta) is now available

ACOM Director Plus 0.6.0 (beta)

This release contains quite a few improvements and will be the last release for a couple of weeks while I work on adding ACOM2000A support. As I have limited access to an ACOM2000A now i’m expecting this to take around 2 weeks to complete.

Changes in this version are:

  • IMPROVED: Carrier Frequency, Gain and SWR readouts altered to improve display time of these values
  • IMPROVED: PA Temperature is now rounded to nearest degree C
  • IMPROVED: VCC5 is now rounded to nearest 0.1V
  • IMRPOVED: Relay Voltage is now rounded to nearest volt
  • IMRPOVED: PA DC Current is now rounded to 0.1A
  • IMRPOVED: PA DC Power and PA Dissipated Power are now rounded to nearest Watt
  • IMPROVED: Bias Voltages are now rounded to nearest 0.01V
  • IMPROVED: Gain now rounded to nearest 0.1dB
  • IMPROVED: Logger integration code refactored to allow easier integration with more loggers
  • IMPROVED: Forward and Reflected power meters now hold their value better improving readability
  • ADDED: Additional compact control panel design, smaller display with just the essentials
  • ADDED: N1MM+ Interface for frequency tracking
  • ADDED: Logger Tracking is now functional (please note that certain firmware versions of the ACOM600S are known not to work, the latest version does however)
  • ADDED: Proper detection for when the amplifier is shutting down

ACOM Director Plus 0.5.2 (beta) – Update for ACOM1200S

ACOM Director Plus 0.5.2 (beta) is now available

ACOM Director Plus 0.5.2 (beta)

This is a minor update containinng a couple of bug fixes, however if you use an ACOM1200S you will need to update to this version as it corrects the amplifier detection to enable proper operation on the ACOM 1200S

  • FIXED: Changing logger integration settings didn’t take effect until ACOM Director Plus was restarted
  • FIXED: Amplifier model detection was not operating properly when using an ACOM1200S

ACOM Director Plus – Beta 1 (0.5.1)

ACOM Director Plus (0.5.1) beta release 1 is now available below

ACOM Director Plus 0.5.1 (beta)

Changes in this release are as follows:

  • Added proper installation routine
  • Added fault display for ACOM600S and ACOM1200S
  • Fixed bug where a crash occured when connecting using a COM port that no longer exists
  • Slight layout and visual changes in the user interface
  • Significantly improved support for windows display scaling (not perfect but much improved)
  • Keep on top option is now functional
  • Some code internal cleanup



Installing Feedlines

After having been off air for a number of years due to an impending house move, I finally moved to my new location last summer. The house is very much a project house so most of last year was spent working on the property. This year however I decided it was time to begin getting my station built and getting back on air.

The new property has an excellent section of land which is ideal for antennas however given that the shack is in an upstairs bedroom getting coax and control lines to it would be a challenge, especially as i’d have to get these through the garden without upsetting the XYL too much.

I decided the best approach was to bury the cabling under the garden. I chose to use Messi & Paoloni BROAD-PRO 50 Double Jacket coax, it provides excellent performance at a fairly reasonable price and with the double jacket can be direct buried if needed.

Despite having the option to direct bury the coax, I decided to use conduit, this would allow me to run some additional cabling and in the event any of the cabling needed replacing, I could do so without having to dig another trench. I used 40mm waste pipe as the conduit, it’s pretty cheap and works nicely for this application, the conduit was laid on a bed of sand to help protect it from any stones or rocks. It was only buried about 8-10 inches from the surface.

Feeding the coax through the conduit was a challenge as I had a few bends, I first ran a string line through using a shop vac to suck the line from the other end (this was surprisingly effective), however feeding the cable through 20 meters of conduit was quite a struggle.

I ended up with 2 runs of coax and 2 runs of externally rated CAT6 cable (all antenna switching control, tuning control etc. will be done over ethernet). I installed an intermediate junction box before the cabling entered the conduit, this will allow me to add additional switching and/or replace any damaged coax without the need to remove the runs that go all the way to the shack.

The cabling exits close to where the antennas will be located and will eventially be terminated in a large IP65 wall cabinet which will house all the antenna switching gear and matching systems, however for now I have them hooked directly into a DX Commander multi band vertical that my good friend Callum M0MCX kindly donated (http://www.m0mcx.co.uk).

I’m very happy with how it all turned out and the trench is now barely visible in the garden.


ACOM Director Plus – Alpha 1

ACOM Director Plus Alpha release 1 is now available to download

ACOM Director Plus – Alpha 1

Changes in this version are as follows:

  • Tray Icon menu now implemented as per the original ACOM Director
  • Storable configuration options implemented
  • Auto connect on startup added
  • DXLog and Logger32 interfaces implemented (Does not yet track frequency through these)
  • ACOM1200S now supported properly, the interface changes scales depending on whether an ACOM600S or ACOM1200S is connected
  • Improvements in connection and communication reliability
  • Implemented Multi-Protocol support in preparation for ACOM2000A support being added in a future release
  • Added system tray notifications
  • About dialog implemented
  • Various bug fixes
  • UI now changes to a disabled state if not connected
  • Slight changes in UI graphics

The following are known issues:

  • Display has issues when using windows 7 with display scaling enabled and set to anything other than 100%

ACOM Director Plus can be installed side by side with the original ACOM Director software.

I would be particularly interested in hearing from anyone with an ACOM1200S as i’m unable to test with this amplifier.

ACOM Director Plus – Technical Preview 3

Technical Preview 3 is now available and can be downloaded below

ACOM Director Plus – Technical Preview 3

This release will be the final Technical Preview release as i’m now working on the initial alpha version.

The changes in this version are as follows:

  • Improved Forward and Reflected Power Meters, they’re now more in keeping with the one on the ACOM display with improved peak value hold and decay
  • Slight change in UI colours and visual appearance to closer match the real amplifier
  • Some of the statistics have been renamed to be more appropriate
  • Improved Stability during connect and disconnect from the amplifier
  • Many background changes in preparation for Alpha 1 release

I would be very interested in receiving any feedback regarding ACOM Director Plus.