The ONLY interfaces on eBay to have been accepted and approved by the deveopers the Ham Radio Deluxe software.
No point paying more for many "lesser" eBay copies when the best simply costs less !
For whatever CAT/Logging software you use.

Using the ZLP Electronics eBay CT-17

If you have the CT17 with built in CW, the lead with the yellow marker is CI-V and the lead with the red marker is CW.

[1] Plug the interface 9 pin D type connector into you comport.
You need to know the correct comport number as you will need to set this in your software. [see below].
If you don't have a comport these interfaces will work with a USB to serial interface cable and often have better noise performance than an equivalent USB interface when used this way.
[2] Plug the 3.5mm jack CI-V/CAT connector into the radios 3.5mm CI-V/CAT socket.
Not the radios extension speaker.
[3] Configure your software so as to raise the comports "DTR" line.
The interface is powered via the comports DTR line.
[4] Configure the software to the baud rate as set on the radio (consult your manual).
Software and radio baud rates MUST match.
[5] Configure your radio so that the CI-V address of the radio is set to the default.
You can change the CI-V address (for advanced users with multiple radios on the same CI-V bus) but you must also change it in your software.

Click "connect" or whatever your CAT / Logging software requires to connect to the radio.

[6] IF your interface also has the EXTRA HARDWARE PTT option (an extra lead with either an 8 pin din or 13 pin din plug),
you can configure your software to activate PTT via the "RTS" line.

If you are using a USB to serial interface cable / adaptor, then it MUST be plugged in BEFORE starting your software.
I DO NOT RECOMMEND AUTO-DETECT, THIS CAN GIVE MISLEADING RESULTS.

If you have problems identifying your comport, download, unzip and run the loopback test program.
The loopback test the interface and also identify the comport used.
It will report "Comport[x] appears to be a ZLP cable". (or similar).
Set your software to use comport [x].
If all fails try a rest on your radio and repeat the above.
If the test suceeds then the interface is fully functional.

 

Performance compared to one often seen, lesser performing version on eBay
Our interface is the trace on the left whilst the often higher priced, lesser performing copy is on the right.

Performance Tests showing low noise performance

 

Noise when using ANY CAT interface. Although rare, from time to time I get questions regarding noise being picked up when using HRD and CAT interfaces. Typically, something along the lines of; "No noise on 10m 15m and 20m, but noise on 80m" What is it and where is it coming from? There are of course many forms of "noise", by far the most common when using HRD and CAT interfaces is the noise that's generated from your very own PC (or some peripheral attached to it). This noise can vary from, no noise, to a permanent S9+. It's most likely the noise from the PC simply being picked up by your antenna "system". A good antenna system will pick up very little noise, whilst an antenna system with one or more problems may pick up so much as to make CAT unusable. If you have "noise" being picked up, you can easily determine if the noise is being picked up by your antenna system… [As there are other factors including separation between PC and antenna, not everyone with a poor antenna / radio match will suffer]. Simply disconnect the antenna from the radio. If the noise disappears then you are on the right track and you have confirmed that the noise problem is actually an antenna problem. Your antenna should not pick up vast amounts of noise from your PC. (That's assuming that your PC is a reasonable distance from your antenna). You can then try unplugging everything on your PC in order to determine if you have one or more "noisy" peripherals. The first course of action is to look at your antenna system and ask some simple questions… [1] Is the antenna a good match to the coax that's feeding it? If your using any form of tuner at the side of your radio then the answer will probably be no. Inevitably your antenna will be prone to pick up any noise - the match between your radio and your coax will in most cases be good 50ohm to 50ohm and you should put the tuner between coax (50 ohm) and antenna (who knows what impedance?) where it will function correctly. As well as removing any PC noise, this action will also vastly improve your stations general performance. [2] Is the antenna being used on the band(s) it's designed for? If not then you probably have a bad match and may be prone to pick up noise. So, how do I get rid of the noise? - Simple, use an antenna that has a good match to your coax. (or use a tuner in the correct place). And use it on the bands where it functions correctly and doesn't pick up all the PC noise. If you want to use a good antenna on other bands where its not designed to be used you can expect to pick up some noise, generally speaking, the worse the match, the more the noise. You may be able to reduce some of the noise to a lesser or greater extent from radiating from your PC unplugging any "noisy peripherals" that may be contributing. But as always, you should first pay attention to the antenna where the majority of problems seem to occur. Want to experiment? Noise can be picked up by simply making a small random length wire antenna (3ft of equipment wire will suffice), plug it directly into your radios antenna socket. Connect the CAT and see the noise rise. Then plug in a decent antenna and watch the noise drop to zero.