KINGSQUEAK.ORG & KC2RGW.COM

What is dosbox? DOSbox home page

It is a free/open-source DOS emulator that runs on many operating systems.

It runs DOS inside a virtual machine in a much more true native mode than running a DOS command window inside Windows XP.

What does this do? It allows for old original DOS software including radio programming interfaces to run on current computer operating systems or hardware.

The issue it fixes is that many old DOS applications relied on the speed of the machine running it for handling timing and interrupts. On current hardware, this means the old software runs too fast and is unreliable.

Also, old DOS software wasn’t aware of things like USB to serial adapters and other new hardware.

This software allows you to create virtual bridges between a new serial port USB device and old ‘com1′ only DOS software.

What have I tested it with so far?

I’ve used the CE14 software for Vertex LMR radios inside DOSbox and it make it work perfectly. Whereas with Windows XP on a 1+GHz laptop, it would run, but not function properly.

You can tell you have a problem this may fix, when the software runs, but you don’t get actual read/write performance to the device you are programming. This can cause a lot of errors with the hardware and possibly even brick the firmware if you aren’t careful.

So, go get it…

Go to http://www.dosbox.com/ and download whatever version you need for the platform you are running it on. Follow the basic download and install instructions.

After install…now what?

So you have it up and running now. These are the steps using a USB serial adapter and programming software.

First, you need to map your com port, using Windows XP as an example. The USB adapter is com4 , you can find this in Windows device mgr, right click on My Computer and select ‘manage’ and then ‘device manager’ and inside there, LPT and com ports. You will see your USB device in there if the driver is properly installed and the com port number it has.

So to set/map the com4 in Windows XP to com1 inside of dosbox while it is running do the following

Z:\>serial1=directserial realport:com4

This will make com1 inside dosbox map to com4 in Windows XP directly.

Next you have to ‘mount’ your path to your programming software. To make this very easy, I just copied my folders for CE14 into the root of C:\ as in C:\CE14\ that is where CE14.EXE lives.

The command to mount inside dosbox is

Z:\>mount c c:\ce14\

This is specific for me as c:\ce14\ is where my software is, replace this with whatever you have, wherever you put it.

Now to get to that location you just do

Z:\>c:

Now you see C:\> as the prompt

C:\>dir

Will show you what is in there. In my case I see all the CE14.* files so I do

C:\>CE14.exe

Now the software runs.

The only thing left to know, is you need to go into whatever app you are using and tell it that the serial port to use is ‘com1′ as that is what we mapped earlier.

DOSbox allows you to map serial1 serial2 serial3 serial4 to four external serial devices, they are treated as com1 com2 com3 and com4 respectively.

You can also map multiple paths to multiple ‘local’ DOSbox ‘drives’

mount c c:\path1\
mount d c:\path2\

At the prompt to switch around you would just enter c: or d: and you’ll toggle between the paths. Just typing ‘mount’ will list what you have configured.

There are a bunch of neat features to control slow down and speed up within DOSbox so definitely check out the documentation links on their site and also try the Z:\>info command as it has a bunch of on line help within the application itself.

The immediate applications for this are with old DOS based radio programming software for LMR radios, but I can imagine that many crusty DOS based packet radio apps and other things will run a lot better in it too. I’m not much of a gamer, but it’s evidently quite effective for that as well.

I think this should cover it.

73 de KC2RGW

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So, I’ve had this device for about two years now and have mentioned it to several people on the air, describing just how effective it is.

What is it? This is an active DSP audio noise eliminator filter manufactured by BHI Ltd.. As simply as possible, it wipes out background hash band noise. It isn’t a pulse noise eliminator like a noise blanker, though it will drastically soften the edge of pulse noise as well.

This is an AF (audio frequency stage) DSP unit. It plugs into the audio output of _anything_ you want to feed through it and you in turn loop it’s output into the speaker or other destination audio feed of your choosing.

The unit has either 4 or 8 steps of increasing DSP elimination effects. In stronger conditions you can back it off easily so it isn’t as heavy handed on processing the signals, or in lousy conditions with weaker signals, you can really clamp it down for the maximum effect.

The best way to show you what this does is simply an mp3 file I created to demonstrate its effectiveness.

Here is a 40m SSB clip with the filter being toggled in and out

The clip was made with some high noise levels and relatively low signal levels at or below the noise peaks, using my vertical on 40m SSB.

The DSP setting was on maximum 8/8 so there is some minimal artifact on the audio signal and a very slight audio level drop. Keep in mind the completely annoying original signal. With the DSP engaged it would be easily possible to maintain a pleasant extended contact with any of the stations in the recording, vs only wanting a brief ‘in and out’ style contact before getting sick and tired of the noise level. A slight bit of the ‘under water’ artifact is much more tolerable.

These units are available in a few configurations from BHI Ltd.. They come in built-in modules designed to be hard wired into the audio circuit of a radio or to be built-in to the internal of a speaker cabinet. They also come in self contained powered speakers with the module included internally. Lastly and my personal favorite are the ‘universal’ inline modules. These allow you to use whatever source or speaker you choose by simply plugging in different inputs and outputs to the unit. It’s the most flexible option.

These modules aren’t cheap, but they are worth every cent if you like to spend a lot of time listening.

W4RT.com is one source in the US for this product.

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I’ve been up to a bunch of fiddling lately and haven’t bothered to do an update here so for posterity’s sake…this is what I’ve been doing.

I’ve always been curious about repeater operations and recently got the opportunity to play with a 440 repeater a friend bought. Boy has this been an eye opener.

We started out with it on a 40′ home Rohn 25 tower and just wanted a low profile machine to cover the local township. Well, we couldn’t use it at a distance of just a few miles. So we found another tower location at 100′ and figured….”now we’ll be in business”. The 100′ spot at 20W output got us maybe 7 miles. Fast forward and we found some people who had a 275′ location and a decent amp and pre-amp as well. Now we’re cooking.

There is a lot of work behind having well balanced link system audio with repeater systems. A lot more than I realized. We’re in good shape now and it’s been an interesting learning experience for sure. The machine is now linked into five others and it’s a lot of fun having a nice wide coverage area.

So on to the IF tap on the TS-2000. What is it? Well, an IF tap brings out the intermediate frequency at the mixer level of a receiver so you can use it for external processing. In my case specifically it’s the 10.7MHz 2nd IF that I’m feeding into my QS1R SDR receiver.

This lets me tune using the Kenwood TS-2000 and use all the filtering benefits and spectrum display of my SDR. This also gives me 2m and 440 coverage via the SDR which I didn’t have before doing this mod. The SDR does 500Hz to 52MHz or so natively.

I used a kit that Andy made up WA5UP that makes it nice and easy. It’s a JFET buffer. The purpose of the add-on board is not only to tap in to bring the IF out, but to prevent any oscillated interference from my receiver from getting back into the HF rig.

The concept for this is hardly my own and I used the document that K4DSP produced that I have kicking around over here. Thanks to both of those guys for making this simple for me.

The whole thing worked out fairly smoothly. I had to bypass the output attenuation in the kit to get a strong enough signal for my receiver, but once I got that figured, things were working well. The TS-2000 shows me about 7kHz of spectrum above where I’m tuned on SSB and about 16kHz below where I’m tuned. This is far narrower than the QS1R generally shows me, but I can now see 2m and 440 on my panadapter and use all the SDR filtering for receive that I have available.

Basically this gives me yet another option as to how to use my SDR rig in the shack.

All in fun and I managed not to burn anything up with all the fiddling too.

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I haven’t really updated much lately, just been busy playing with this or that.

Just got one of the Zero Five 10m 5/8 verticals in the mail. Man, this thing is built like a rock. It’s actually a bit too solid as the quickie makeshift mast I was going to throw it up on will now have to be something a bit more substantial.

The base diameter tubing is roughly 1-9/16″ O.D. and the thinnest is about 5/8″ at the top. Very heavy quality aluminum and well put together construction quality for it’s tuning ring matching system. I went with this one in the hopes of having a very solid build quality and so far so good. Can’t wait to get it in the air, but I have to get myself a TV tripod to mount it on.

I’ve been tinkering around with the QS1R SDR GUI interface SDRMAX 3.0 again lately. I committed a bunch of changes to the project trunk for button layout changes, added filter options and also darkened the overall color scheme for some better contrast. I’m still amazed at all the work that the original author Cathy Moss put into this software.

I’m still barely just a hack with Qt and C++ so I’ve basically just been reverse engineering what she did and just poking about with superficial changes that I can follow and get to build properly.

The good news is that Qt 4.5.2 just got released and has fixed all the OpenGL font rendering issues that the Qt project claimed weren’t broken with 4.5.1. Nice to know that at least when they won’t admit any issues, they at least fix them. Now our project doesn’t have to keep tarring up 4.5.0 to give to people who needed a clean build source until they fixed it.

A screenshot of the enhanced contrast and my own hacked in color scheme for the panadapter and waterfall in SDRMAX 3.0.

changes to SDRMAX 3.0 interface

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SDR Software Defined Radio – KINGSQUEAK.ORG.

I’ve started fleshing out a bit about SDR and how I’m involved in it and what it actually means and does.  If you are a radio nerd like me, a ham or an SWLer,  I encourage you to look into SDR.  It is amazing stuff.

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