KINGSQUEAK.ORG & KC2RGW.COM

So, this looks a lot like a CB microphone doesn’t it? Well, it is. Sometimes you find some equipment that serves multi-use environments nicely and this is one example.

This is a ~$20 (less than half the price) Chinese knockoff of the Turner Road King 56, called the Overdrive CDL-56k. It is a dynamic noise-cancelling element hand mic. I stress noise-cancelling as this thing is very effective to knock out background noise.

I’ve been using an Astatic 636L in my Jeep Wrangler in the nicer weather as I drive around with the windows down and music blasting and don’t want all that racket to get into my signal on the ham bands. It also works well, but has a very restricted audio passband so it makes the transmit audio sound very tinny.

I found some mentions about this Overdrive mic saying that it had a more natural sounding audio response and decided to get a pair of them to play around with and find out.

The results have been excellent, both on FM repeaters and simplex and for SSB use as well. I’m using them on an FT-857D in my mobile and on a Kenwood TS-2000 at home when I feel like using a hand mic.

I highly recommend this mic if you have a need or want for noise-cancellation. For what it does, the audio response is very good. This type of mic will require you to speak right into the mic element or your voice will just disappear. That rubber ridge on the face should be touching your upper lip while talking. If you talk farther back from the mic, this is not the mic for you, nor will you get effective noise cancellation from it.

The mic has plenty of drive to work with either one of my rigs. I’m not sure if it would work with a ‘normal’ amateur 2m/440 rig directly without an added pre-amp though, but I haven’t tried it. It would surprise me if it had enough drive for those typically 2kOhm inputs though.

Driving down the road at 60mph, windows down and music deafeningly loud, people barely even notice it at all while I’m talking…mission accomplished.

I picked mine up from Premiere Electronics and have done business with them in the past for parts and microphones. They are fairly widely available from other sources too.

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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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This map shows ham station beacons and the trails of moving vehicles on APRS

Well my IF tap worked great for a few hours and after I shut down my rig….signals were not right. I learned what seems to be a fundamental lesson about JFETs…they don’t like static much. I’m 99% sure that I zapped the JFETs in the buffer amp I installed after doing some reading on how static sensitive they are. At least my rig is just fine otherwise.

So I got an alternative design buffer amp that’s sitting here waiting for me to pop the hood again and install it. This one doesn’t use JFETs, so my gorilla paws without a static mat won’t be as likely to cook it.

In other news, I’ve rewired myself again for packet radio and APRS operations. Using Xastir on Ubuntu linux, I’ve had APRS up and running a few days consecutively here and there. Pretty neat stuff and can be _very_ handy for any mass deployment events.

In a nutshell, APRS takes GPS coordinates or other information and sends it out as a beacon via radio. So if I’m running the mapping and client software and you are in the field with a handheld running APRS, I can see your position as it is beaconed every few minutes overlaid on a map.

If you are providing event support over an entire marathon course as an example, as the control operator or other field station, at a glance you would be able to see the location of all your operators. This becomes important when you get a call that a runner or rider has been injured and needs first-aid. The closest support vehicle can be instantly located. Not only that, but you can follow that vehicle on the map and know when it arrives at the hospital or control point.

You can beacon most any data up to a limit of 40 characters per beacon. Commonly people beacon their position and then a frequency they are listening to. This way when you see them up close, if you see them you know how to reach them. It can be fun while traveling around just to make contacts as you ‘run into’ them.

Generally this is all done on the 2m ham band for local coverage. But even with that system, there are facilities to repeat or ‘digipeat’ the traffic a station hears. So if I beacon, a station within range will hear it, and then transmit again. Yet another station further out will pick that up and repeat it again, and so on. Add that it is also possible to send the data out to the internet from home stations and you can reach pretty much anyone on the network, world wide.

There are even low frequency links that will broadcast the traffic hundreds or thousands of miles in a single hop. This can all be incredibly useful in the even of a major disaster that knocks out telecommunications services. Hams have the ability to set up field stations with these capabilities in a matter of hours. It’s something not often remembered about this ‘hobby’ as witnessed here ARRL article about the Haiti earthquake

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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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It’s indeed been a scanner day here at the shack. After having it annoy the hell out of me for several years, I finally got around to replacing the EL (electroluminescent) back light for the display on my old Radio Shack Pro-2006 scanner.

Found the tips on how to do it at Radio Reference thanks to one of their forum users. The part was all of $3.50 from All Electronics one of my favorite quick grab parts-bin sites.

Now it’s as bright, if not a bit better than it was new, 15+years ago.

The surgery to do it was a bit deeper than I’d expected with a few annoying ribbon connectors to un-wedge and the usual myriad of small retaining screws, but once the adhesive blob was cut and the two leads desoldered, it was a piece of cake getting the new EL panel in there. Worth doing.

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I’ve always liked scanning receivers, radio of any type really but scanners are an addiction. For some reason I’d taken a break from running scanners for a number of years and recently I dusted off some of my old reliables and remembered how much I enjoyed general public service monitoring.

I decided to take the plunge and get the latest and greatest digital and trunking capable model to augment the old reliable Radio Shack Pro-2006 that is still humming along. This gives me the capability to monitor the newest radio systems as they come on line in the area.

Currently in my part of NJ there are not that many digital systems, but across the country they are coming on line very rapidly, so if I was doing any traveling this new portable would come in quite handy.

I’ve only had this for a few days now and it’s taken a few days just to get a basic handle on all of the features. This thing has any feature I could have imagined missing on the old banks based scanners I’ve owned before. For anyone considering either the Uniden 396/996 or GRE PSR500/600 series, you simply *must* anticipate using software to manage the memory systems and also anticipate using an online database for frequencies if you truly want any ease of use.

So what are some of the advancements vs my scanners of olde?

Sheer capacity. My Pro-2006 was considered a very high capacity scanner when I purchased it with ten banks (selectable groupings) of 40 channels for a total of 400. I used to think I would never be able to fill that up. The 396XT has a capacity of 25000 Channels! Suffice it to say I think I could program most of the entire East coast with the capacity this thing has. With programming software linked to the on line frequency databases, you can put an awful lot into the unit in a very short time.

Memory management. In the old days you had the bank system. Ten banks of 40 channels as an example. You use the banks to turn scanning categories on and off. Putting police or the local town in bank 1 and adding neighbouring towns or other categories in the other banks. This is a fairly simple system, though if you only have ten channels in bank 1 that you want, you wind up leaving 30 unused memories blank. This is very wasteful. Also the old scanners only showed you the frequency information on the display. This made it hard to know who was talking as you had to memorize them.

The new world has gone to an object oriented approach that takes a bit of fiddling to get one’s head around. There is a hierarchy of categories. System/Site, this is the top of the chain, generally a regional name, though you can make it a top level category of frequencies as well. Next up is the Group, a sub category, a township name as an example or “fire analog” or “fire digital” if you wanted to group in that way. Then finally inside the groups are the frequency entries.

There is then a ‘cross index’ of sorts. So you have your System->Group->Channel hierarchy, you can then tag those with ‘quick keys’ or index numbers that serve to enable or disable them on the fly. This allows you to do a quick select of a global category for monitoring. In trunked system mode you have System->Site ->System Frequencies->Channel Groups->Channels.

An example that I’m using

For daily scanning I have two main System categories, “Home” and “Locals”. Home consists of my immediate town and the singular bordering townships. The groups underneath “Home” are named for the neighboring townships or miscellaneous categories of other immediate resources like “ham repeaters” Locals are the next ring of neighboring towns, two or three towns ‘out’ from where I live. Places I can clearly hear on the portable and may be of interest. The groups inside Locals are also townships or general categories.

Now, Home and Locals have a quick key of 0 and 9. So while scanning I simply enable those two quick keys and those two systems are in turn actively monitored. Inside the Systems, I have the groups. Each of those group assignments have their own ‘quick keys’, the purpose of this is that I can enable Home and then enable and disable the groups inside Home itself. Example, enabling Home and the group quick key for my township only if I don’t want to hear the immediate neighbors for some reason.

O.k. so you have that control…what if you have say a public works frequency in the local town grouping but you don’t normally want to hear that? You simply use the old style lock out function. This just blanks the channel while scanning…skips right past it. You can manually queue it up if you like or unlock it if you want to hear it for a specific reason. Alternately you can make groups like mayberry-PD mayberry-FD mayberry-MISC and assign each of those a GQK (group quick key) so you can simply enable or disable them with the group quick key.

This is a bit complex, but it is extremely powerful and leads to fantastic flexibility if the user just takes some time to adjust to it and figure out how they want their own categories laid out. After four days or so now, I’m still in the process of optimizing the layouts for my general preferences.

As mentioned earlier, software is absolutely *key* for managing all of these categories. I am using Freescan , a free application that is under rapid and current development and supports all the features of the very new XT model that I own.

One of the huge functions that Freescan provides is the ability to import files locally, save your configuration locally and the big one…use an internet connection to an online database and load frequency plans that way. I highly recommend Radioreference.com they have free access as well as a subscription that permits online loading directly from their database. The site is also a fantastic source of information on most models of scanners and information on the monitoring hobby in general.

Enough rambling, I tried to keep this as much to the point as possible, but it’s a ton of information to cover. Suffice it to say, if you are looking for something to entertain you for days at a time, the newest scanning receivers from Uniden and GRE are simply incredible.

A few links on the topic:

Some Vendors:
Scannerworld.com A vendor that provided quick service that I recommend.
Universal Radio Another vendor that I use as well, also recommended and have a great site for pictures of the products.
Uniden/Bearcat Main Product Site
GRE America Main Site

General Information Resources:
Radioreference A site with a frequency database, live audio feeds of scanners, a wiki and active forums…highly recommended!
Uniden Product Wiki Reference The home of a lot of their on line info on scanner operation.
Eham.net Scanner Reviews Take with a grain of salt
For publications, there are Popular Communications and Monitoring Times both have been around for quite a while.

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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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ARRLWeb: ARRL NEWS: DREAMing Big at Dayton.

The Hamvention, where all the major vendors for ham radio make their annual product release showcases and announcements.  It’s the CES for ham radio.

Didn’t make it again this year, but one of these years I’ll get out there.

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In amateur radio there are many modes of operation. Modes where you use your voice, modes where you work behind a keyboard, modes where you drive a code key. There are options for anyone.

I work many of them but my favorite mode is simply ‘phone’, using my voice to speak to others. Meeting the different personalities and hearing the different voices is the primary reason I enjoy this hobby.

The Marconi Net is a structured round-table discussion with a central moderator or “net control station” (generally Fred, KB2IXT). The net runs most evenings at 9pm on 3.872MHz. The way it works is simply the net control asks for check-ins and people from around the region give their call signs and get added to the role call. The net control station simply calls the role and each person gets their turn to toss their own comments into the ring.

What makes this net interesting is the coverage of many topics, from current events to hobby related technical topics. Almost anything goes. One meets people from many backgrounds so the topics can vary wildly from night to night. The participants almost always take the discussions to a more elevated level than the general “sitting around the pub” level of conversations that are much more prevalent on the bands.

I encourage anyone in the hobby in the north east region to stop by and see if it is something that would appeal to you. All are welcome.

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