Scooter CB, modified headset tests

Having modified the headset connector cable in a different manner to what I would have liked, though using more or less the same principle, I put it under a couple of tests to see if it did exactly what I hoped it would do and I am pleased to report that it indeed works properly, the modifications were as follows:

1. The cable between the PTT button and  the radio was cut before a join in the cable that has 4 cables coming out of it, the PTT wires were then closed and taped over,
2. The cut section was then prepared to go into a new section between the mic jack of the radio and the mic plug on the headset
3. A new connection was made, this was built using some spare wire I had lying about, two new 2.5mm connections, one plug, one socket, the PTT switch disconnecting the tip of the 2.5mm socket when not pressed, and reconnecting it when the button is pressed

As a result, the Midland Alan 42 Multi handheld that will be the scooter CB now switches between transmit and receive correctly, this means I simply need to add the antenna, EGP, and a cable to connect them to the radio, and I'll be on the air on my scooter in no time, all in all I am impressed with what I have achieved, I can also swap out the current lead for a Kenwood-type for my Wouxun dual-band handheld in the future should I wish to use mobile on the scooter it once licensed on the amateur bands

I look forward to testing it out on a proper antenna.

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

Scooter CB, proposed antenna arrangements and a bit more updates

Now, the scooter will need an antenna fitting, however it needs an artificial groundplane, and there are at least two options.

The first option is to use the Sirio GL27, this comes with a mirror bar mount and thus would mount onto the scooter's luggage rack, however this antenna is supplied with a cable that cannot be cut short thus making installation somewhat difficult without raising the antenna high up, not ideal as I cover my scooter every night and need an antenna that will fold out of the way.

Option number two is one of those electronic ground plane devices from 4x4cb.com, this is a plasic cylindrical device that an antenna with a 3/8 thread screws into the top of, and the coax cable screws into underneath, I can simply fit this inside the top box and the antenna screws into the mount on the outside of the top box with the cable exiting underneath.

After running the loading test the other week (and at the same time proving a man who likes to claim he knows everything about motorcycles and likes to call himself "Goliath" when that isn't even his real name as being completely and utterly wrong) I am free to move onto the commissioning of the scooter CB, it will be ideal as it means I'll be able to use the 27MHz Free Radio Network gateway in Richmond, and perhaps do proper range testing with it as I have not had that chance.

With a major cause of problems for me now out of the way my focus can return to radio and the like, I am currently monitoring my PMR446 gateway at the time of writing this, and feel quite relaxed compared to what I normally would, it even now means I have no contact with the above mentioned "Goliath" who claimed my scooter's alternator would struggle with the load of a CB radio.

So more airtime for me in the coming months, and maybe eventually in the next couple of years I can have a house with a garden big enough for my antennas, which I'd 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