Handheld CB tests

I thought now would be a good time to test out both my handheld CBs ahead of time, the Midland 42 held charge nicely and transmits in both power settings no problem whatsoever, the radio with the power problem is, of course, the Intek H-520 Plus.

Firstly when I found the Intek it was pretty much dead, connecting the charger was the only way to get it working, removing the charger and keying up at 4 watts immediately after plugging the charger in resulted in the inevitable low battery alert and the TX cut out, same at 1 watt, however it lasted about a minute longer at 100mW, to be expected as the batteries were very low charge and are well due a replacement, and I suspect the charger supplied with the radio is absolutely dire and once I replace the batteries I will be charging them out of the radio with a charger rather than in the radio, I initially was going to swap the batteries out with Eneloop batteries however after doing some digging I found 7DayShop do 2900mAh AA batteries for a good price (Eneloop batteries only go up to 2500mAh, same as the Energizer batteries already in the radio), the good thing is that both radios key up fine.

The Grant II is subject to tests next and these handhelds will be used as part of those tests as well, for both AM and FM modulation, for SSB I will have to tune my RTL-SDR to the appropriate frequency I use to do the test as my handheld CBs can only demodulate AM and FM, however I am satisfied the CB HTs are both working as they ought to be.

These tests are required as a prerequisite of setting up internal comms for myself and guest(s) at the National Hamfest, once the H-520 batteries are replaced then I can focus on running more tests.

73 de 26CT730/2E0EIJ

T2LT revisited

I've been on an antenna theme recently, what with both a Slim Jim and a 2-meter dipole written about (the latter being made, the former an idea I can put to some use), and I continue with a favourite CB antenna of mine, the T2LT, the person who made the original video showing how to build this antenna, Gary 26CTX104, remade the video into a two-parter where he went into a little more detail and built another T2LT, it turns out the video was published well over a year ago and I'd not done a lot of CB at that point and was just starting out on Amateur radio, but CB is a bit of fun now and again but some good contacts can be made on 11 meters depending on the solar cycle amongst other things.

So, as you will know I already have a T2LT antenna built, and have tried it out but using only 4 watts into it (perhaps less on battery powered rigs as these radios are designed to run on 13.8V DC whereas my sealed battery is about 12 volts and a pack of AA batteries don't deliver much for long, handhelds are not counted here) though conditions were not favourable for me

So, the plan is this, get the antenna up on my fibreglass mast, inserted into a parasol base or attached to a secondary mast (no more than 1.5 meters) that will fit a parasol base (this avoids planning constraints as the antenna can be removed with relative ease), run a feeder to my "shack", plug the Grant II into it with my good SWR meter for CB in line (I have 3 CB meters and one VHF/UHF meter) and check to see how well it is tuned up, and try and make some CB QSOs (using my CT call if it is still valid which it should be), naturally I will be carrying out some other tests, I just need a volunteer to sit in the "shack" to transmit, as it's CB and anyone can use it without needing a license, for that test the CB magmount will go on my current car connected to the car adaptor of one of my handhelds, the Intek H-520 would be ideal for this as it has a large readable S-meter over the Midland Alan 42 Multi, though both have an S-meter.

So, I am keen to give this a go so Saturday will be a shopping day for some bits

73 de 26CT730

Tan Hill pre-DXpedition evaluation - video

Here is the video I took up at Tan Hill, it's taken me a while to get it ready for putting on here but I got there, it should give you some sort of idea of what I was talking about in my last post.

73 de 26CT730

DXpedition preparations, parts list and rough measurements for T2LT antenna, and a possible cheap and light power supply

As I am hoping to order a 100 meter drum of coax, specifically RG58, I have taken some measurements for the T2LT antenna, I may make a second antenna for home if the design proves itself in service, the measurements are those used by YouTube user UKCBTV, a fellow Charlie Tango station (though can't remember the callsign), with a working centre frequency of around 27.500MHz, should cover the legal 80 channels with little in the way of trouble.

Another thing I found while watching UKCBTV's videos was his excellent idea of a portable power supply, which uses 10 1.2v rechargeable batteries, which range in capacities up to 2500mAh, that would be roughly 25Ah at 12v DC, so something I may cobble together, as well as get hold of a decent battery charger plus some new batteries, he also fitted a volt meter, a good idea to ensure voltage is stable and a cigarette lighter line socket, the battery box and cigarette lighter line socket can be sourced from Maplin Electronics, the voltmeter appears to be an eBay purchase.  This idea was compared to the Midland 77-805 Portapak CB radio, which had a battery box with it, handhelds are another option but the battery life in most is usually pretty dire and the rubber duck antenna is usually hopeless.

The current draw for my Midland Alan 78+ Multi B is around 1.1A on TX, presumably at full modulation, the 42 handheld (which includes a car adaptor) is slightly shy of 1A on TX, the President Grant 2 is 3A on TX with modulation. my Moonraker FA5000, which I now hardly use, I do not know the current draw for as I've lost the manual.

So if I can get the T2LT antenna built and tested in the next couple of weeks, I can focus on a suitable power supply, the battery pack idea above from UKCBTV sounds ideal and is cheaper and lighter than the car jump starter I was originally going to use and will get me started, a telescopic fibreglass mast, and, importantly, a shelter, a collapsible tent may suffice, and a means to carry it all on my back while riding my scooter (I don't have a car yet) then I'm  all good to go, and can get on the air portable at Tan Hill hopefully come August time, if you're on air the day I am up there then we may hear each other on air that day, I'll be using the usual callsign

So, progress in the right direction, power lead, a possible electrical supply, and the measurements for the T2LT written down.

73 de 26CT730

Another scooter CB progress report

Having fitted the earpieces and mic to my motorcycle helmet, I plugged the headset into the supplied cable wired for the radio and found a small problem.

With the cable disconnected from the headset, the PTT functions normally, that is press to TX, release to RX, however, connect the headset to the radio, all is changed, the Midland 42 goes into TX with no power, and pressing the PTT applies the power, this does not occur on my Intek MT-5050, which is a PMR446 set, and running mic-only with the Midland 42 does not eliminate the issue.

The headset is getting a trial run today to see how it handles an actual trip on the road, I may connect the Midland 42, possibly speaker-only, and monitor traffic on the CB gateway channel.

I also intend to connect up the car adaptor temporarily in order to ascertain if the TX issue is eliminated with the earthing of the scooter, if so, then I won't need to modify the headset in any way, otherwise I'll need to modify it as such so that a second switch is needed in order to transmit.

I will report back later

73 de 26CT730

Scooter CB: progress report

The scooter CB project reached another milestone today, the arrival of the motorcycle helmet headset, interestingly made by Albrecht, which is part of the same group of companies as Midland, something I note because the radio is a Midland Alan 42 Multi

The headset came in two parts, the radio connection part with PTT switch, a Kenwood type also exists so I could simply replace this for the Kenwood type to use my Wouxun KG-UVD1P on the Amateur bands once licensed, and the headset itself which is two speakers and a microphone held in by velcro pads.

The connections are all quick to make and disconnect, the PTT uses a DC type connector to connect it to the headset, the headset itself connects using a mini-DIN connector (looks to be 6 pin), and at the radio end there are two plugs, 2.5mm mono for the microphone and 3.5mm stereo (though seemingly wired mono) for the speakers, these are not a combined plug however, they are separate plugs, but this does not cause any issues otherwise.

The earpieces will be fitted to my motorcycle helmet either this evening or later in the week, further progress will be made later on once I have ordered antenna parts and they have been delivered, but I can still do a test run with the headset inside my helmet and a radio with me, weather pending because radios don't like water very much and you know what the British weather is like

73 de 26CT730

private listening issues and progress with the scooter CB

Now, as anyone in the radio communications hobby will know, pretty much every transceiver and scanner is set up as such to have a mono audio output, meaning plugging in a pair of headphones results in a dead left or right earphone, and for me this always causes a level of discomfort.

Today I purchased a pair of Sony MDR-V150 headphones, I have another pair of Sony headphones and have found them to work wonders, if you want good headphones, buy Sony headphones, of course plugging them into my radio resulted in there being one-side not working, not ideal if you want to use them with your radio, so here is what I did.

I used a piece of cable with a TS plug of the sort normally used to connect external speakers into rigs, the bare ends of the wire were soldered into a scrap of veroboard on which I fitted two resistors, originally at 10k Ohm but I reduced this to 1k Ohm as the 10k resistors made it such that I had to turn the volume on the rig and handhelds full up to hear anything when I tested it, I may use lower resistors but the 1k resistors are fine for the moment, the other side is a suitable socket for connecting any pair of headphones, even the earbud type, for this purpose it doesn't matter if the left and right are wired to either resistor the audio is mono from the rig and simply being split to both channels on the headphones, it's a fairly simple solution and cost me nothing as I had all the parts in stock already for at least one such adaptor, possibly two.

The scooter CB issue was approached today since the weather had dried up, QRM only appeared to be present when the starter motor was turning over, with the scooter's engine running QRM was not present, nor was it conducted through the cigarette lighter socket that I had fitted, and load on the scooter's generator was not an issue, even during transmit, this last issue was brought up with me some time ago when an idiot decided to tell me that I didn't know what I was doing and there was no way the generator would handle the load, as the Midland Alan 42 Multi is only a handheld it is designed to be quite energy efficient yet still work as well as a normal mobile rig, and the generator never once complained, even with the scooter's lights on, so an antenna and a motorcycle helmet headset are next on my list for that as of today.

So I am almost on air at home and mobile, and hopefully this week I can begin the journey to licensed amateur.

73 de 26CT730

Midland Base Camp446, the “Swiss army knife” radio

Now I just added a new radio to my motley collection of radios, the Midland Base Camp446, which is a “Swiss army knife” radio, or so I think anyway.  What makes this radio different from most PMR446 radios is that it is equipped with a flashlight, USB charging port, medium wave and VHF broadcast reception, VHF marine band reception, and a dynamo charging system to charge the radio or anything connected to the USB charger port.  It also features an alarm clock and Morse code function to send signals using the flashlight. It comes with both a home charger and car charger, a shoulder strap, and a Midland branded speaker/mic for ease of use, I tested the speaker/mic with my other radios with a 2-pin standard connector, it worked with my Intek MT-5050 but it did NOT work with my Intek H-520 (the transmit was jammed on with the mic connected), the radio features a high and low power setting so as to save on the battery if you are only communicating over a short distance, it is simple to operate, the volume and power control is rotary, which I like in a radio, the tuning/channel change control is a momentary rotary control, turn right to increase channel, left to decrease, a 4 position switch selects the band, a 2 position switch below that selects the battery type, and a 2 position switch below that turns the light on and off, on the right hand side is the dynamo crank, this can be turned clockwise or counter-clockwise to recharge the batteries or phones, MP3 players, iPods, GPS systems, and PDAs that may be connected to the USB socket in the left hand side, the left hand side also features the flashlight, the speaker/mic socket (2-pin), and the charger socket, the rear has the antenna, which folds down, a very large battery box for both the supplied rechargeable battery pack and normal AA sized batteries, all in all a good radio.

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Mods:

Note, For information only, I do not recommend or encourage modifying PMR446 radios, you do so at your own risk

This radio can be modified for increased power output (3 watts), and increased channels (LPD433 on the PMR446 only model), or locked to LPD433 only, or PMR446 only
Inside the unit you need to locate 3 jumpers, these are JS4, JS17, and JS16, the settings are as follows

JS4	JS17	JS16	PMR446 settings	LPD433 settings
0	0	0	500mW H/10mW L	disabled
0	0	1	3W H/500mW L	3W H/500mW L
0	1	0	500mW H/10mW L	500mW H/10mW L
0	1	1	3W H/500mW L	disabled
1	0	0	500mW H/10mW L	10mW
1	0	1	500mW H/10mW L	disabled
1	1	0	disabled	10mW
1	1	1	disabled	3W H/500mW L

EDIT: I discovered a service door (it’s an unmarked piece of thin black plastic) in the rechargeable battery pack compartment during a routine security mark, all 3 jumpers, plus a cut 4th jumper were present, the 3 jumpers were closed, in the above diagram, 0 means do NOT cut, 1 means cut, the order is unknown jumper (already cut by Midland), js4, js17, and js16, don’t touch the first jumper.
The picture below shows the location of the jumpers behind the service door

The 4 loops apear to be steel wire, so you may need some very sharp cutters to cut them, to put the radio back how it was just reclose the 3 loops, leaving the left-most one as is

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I will make a short video demonstration of this radio in the coming weeks, stay tuned
73