Monday, December 14, 2009

USB 2 LPT update

I bought some of the USB to LPT converter cables. I bought first a kit, which has a very fine pitch leadless IC


I've built many surface mount projects and this particular IC proved to be beyond my capability from both an equipment and expertise prespective. I just don't have fine enough equipment and good enough eyes anymore to solder this chip by hand. Fortunately I know someone who does possess such skills so my investment is saved. My strong suggestion is if you purchase this device buy one already built unless you are a SMD expert. I bought the 1.7 revision, but the 1.6 revision is probably adequate for this purpose and is a lot cheaper either built or in kit form. The kit form looks to be perfectly do-able for the average SMD builder. Here is a shot of the ver 1.6


It has as far reduced part count and the main chip is easily hand solder-able but it does not have USB 2.0 speed. Probably that is not relevant for this application.

The reason I was interested in this cable is because my new computer does not have any hardware for LPT. As far as I can tell this is the ONLY true USB to LPT cable out there. There are a lot pf printing cables but that is a different animal from a true USB to LPT. To get the fully built cable to work was merely a plug and play operation. I just plugged in installed the drivers and put the correctly emulated LPT information into DDUTIL and I was sending out properly coded BCD that follows the Yaesu standard band plan.

It works perfectly with my F5K/DDUTIL set up. I added this board:

from Unified Microsystems, and I now have the capability of having band following antennas. What that means is if I click 40M the 40M antenna is automatically connected, or if I click 80M I immediately switch to 80M. Here is a typical set up using a LPT port and the UMS controller board:

Notice you can run 2 UMS cards off a single LPT port aka 20 antennas. One card is connected to Data 0123 and the second to Data 4567. (In fact the USB2LPT driver can be configured to give up to 20 I/O lines but DDUTIL won't address that many)

for 3 antennas, 80M 40M and a tribander the connections are as follows:

Note how one relay is chosen for each band of the tribander. You could do this as well for some of the 5 band beam antennas or for a Steppir. Soon I hope to be able to switch 2 sets of antennas using 2 of the Unified Micro boards on the same LPT port giving the ability of switching up to 20 antennas in a band follwing format. That will require some diddling with the software but it should be do-able.

Why 20 antennas? Actually what I am interested in is 2 banks of 10 antennas. This will bring out the functionality needed for SO2R. This, plus a couple other software tricks will allow full expression of SO2R using the Flex 5K as the foundation and DDUTIL as the Swiss army knife that hooks everything together. I should be able to rig up any number of up to 20 total antennas to any of the three F5K antenna outputs and have up to 3 amps controlled by DDUTIL, so you merely change the band and the appropriate amp/antenna will be chosen including being able to chose RX antennas on either receiver all automatically according to a predefined look-up table. I'm also hoping to be able to do other band following tasks like automatically adding inductance to a vertical based on its freq. For example if the radio is set to 1800 inductance might be added to the 160M vertical but when the radio passes 1900 the inductance would be switched out. This would be kind of like having a poor man's Steppir. You could do the same with those short 80 and 40M beams to toggle between ends of the bands etc. The hardware is there, and the software is almost there, and you should be able to build this for well under 100 bux per board set to control 20 antennas.

I'm still working on making my RCS-4 antenna switch band following but I think the end for that is in sight as well. I have the controlling relay boards built so there is only a little more twiddling needed. I will publish more on that as it comes to fruition.

I also just bought one of these:

Which can be made band following from DDUTIL using the Yaesu BCD data. More to follow

73