Fun with fitting roof bar mounts for antennas

I've fitted roof bars to my car and mounted the two antennas to them, the bars are coated in plastic and their mounting hardware is powder coated, however the bolts holding the fitting kit parts to the car showed continuity to the bodywork, the CB antenna at the very least needs bonding, which I have done using a piece of 27A DC rated cable, but this may be posing a problem itself so I will need a braided strap, while DC continuity is all well and good there could be reactance in the copper cable used, so a braided battery strap is needed instead.

This would be run from the bolts on the CB mount. then one of the bolts holding the roofbar mount fixing plate onto the mounting points on the car.

Using the wire, which is stranded, I got two low-SWR points either side of the CB allocations (SWR remains high within the band) once the mount was bonded, with the wire at the full spool length (2-meters or so) the SWR was much lower but it really needs bonding.

The 2/70 colinear antenna is offset from the centre towards the driver's side of the car, early tests on the VNA suggested that on 2-meters this antenna is working fine so I do not know where the antenna is getting its ground from on that band, I've not checked this on 70cm as yet.

As the VNA battery ran out during tests today I tried to power it from the car charger, this created a ground loop because the car electrical system has its negative grounded to the body as well as is the case in many modern vehicles.

Tomorrow I will pick up a braided earth strap of suitable length and try this on the car to bond the CB antenna as I suspect this copper DC cable I've used may not be working as expected.

73 de M0WNU/26CT730

New year and a catch up and eBay goodies

So we enter 2022, a new year and let's start as I mean to go on, so I did in the end buy the Yaesu FT991A after the tax refund I had but yet to get it on HF due to lack of suitable antenna so that's a work in progress.

I took the time to rebuild my desktop computer, as it was woefully outdated and could not process video fast enough. it is now much improved with the original hard disk being used for storage and the machine booting from a solid state drive, a 4K video renders at about the time the video takes to play back rather than many hours, 1080p videos are also quicker also and do not take hours to do.

I also had to rewire the CB antenna magmount after damaging the coax during a trip to the car wash, it is working fine and the SWR is low, one meter suggested almost perfect but other meters suggested that meter may have been a bit optimistic.

And of course, eBay goodies, I won an auction yesterday on what looked like a well used Midland 38, though it appeared not to have a microphone but the one from my existing Midland should work, as Knights sell these as replacements and suggest them for 38s, I am also watching another Midland radio and will bid on it as long as the price does not go too high and I will report back if I win it or not.

For a radio ham and tinkerer like myself it is no great loss if I buy CBs that do not work as I can attempt to repair them, old kit like this can often have failing electrolytic capacitors which should be replaced at the first opportunity, these are easy to spot, other parts like the PLL chips are a little harder to come by for some of the 80s classics as the usual ones used in those are long discontinued, the Midland 38 is a 1990s set so would not use the LC7136/7. prime suspects for other failures in radios like that is adjusted coils done by "screwdriver experts" who do not have a clue what they're doing, turn things with screwdrivers and break ferrite cores in inductors, though more often than not they set the deviation far too high thinking this results in higher power (it doesn't, it makes the radio sound crap and bleedover adjacent channels). so one tatty Midland 38 in the bag, another less tatty one if I win it could be here.

A commenter on my YouTube channel suggested I buy a K-Po power mic, I won't ever do this because I feel these don't really help matters at all, my desk mic is a power mic but has an awful capsule in it, a speech processor mic perhaps will, the most I'd want in a CB mic is a roger bleep but even then that's pushing it, the same commenter told me that Knights can wire the mics to whatever radio desired, however I prefer to do this myself as I generally prefer to wire my own CB mic plugs.

And on the subject of YouTube  I have a video to make which requires I put the antenna up so I best crack on with that.

73 de M0WNU/26CT730 (or just the red squirrel on the CB, and maybe later this year or next year my spouse will be heard on air once again too)

Yaesu FT818 or FT991A? The decision I have to make

So I have a good pay packet on its way on Wednesday and a surprisingly large tax refund imminent I want to buy a set that can do HF and also 2/70 all modes, as I like Yaesu equipment I narrowed my choices down to two, the FT818 (which is effectively an 817 but 6 watts out at full power) or the FT991A which I have been after for some time, which as a nice colour screen, supports all the bands and modes I want except 4-meters, and also supports System Fusion which is my main digital voice mode of choice, as well as allowing USB connection to a computer rather than the specific cable used on the FT818, and also capable of 100 watts out on HF (50 on V/U).

I am really keen on the FT991A because I've been after one for some time and the space in my shack has always been set up with a FT991A in mind, if I choose either radio though I will be free of one issue at home on 2-meters that has plagued me for so long, pager intermod, I also plan to test out the flowerpot on 2-meters with the final chosen radio, which I strongly think will be the FT991.

Operating HF from the home QTH will pose some challenges, an antenna and possibly noise, which I know there is plenty on 27MHz so the rest of the 1-30MHz spectrum will probably be bad as well, however as these radios run of 13.8V DC then they can effectively be run from a battery so I can go somewhere relatively free of noise with a portable antenna (I am already equipped with a mast stand and SOTApole to do this).

Also I have seen these sorts of radios used on 27MHz on YouTube, this is something I won't be doing as I always run legal power, on 27MHz this is 4 watts, a now not so regular commenter on my videos claims I effectively moan on about CB users running higher power, I do often express my dislike of the practice yes however I also say that if people want to do it the it is up to them and I do not endorse it and I also find it is a waste of money to buy something like a Yaesu HF set to solely use it on 27MHz but again it is their choice to do this.

My initial plan for HF was to get something like the uBitX or similar however with this unexpected financial improvement I think something reliable and robust is in order and a Yaesu radio is definitely the way, and already owning 2 Yaesu sets and not ever had any problems means it is justifiable too.

A YouTube video will be done as well, and hopefully I will find a way to do HF from here as well as the usual 2-meters and 70cm

73 de M0WNU

3D printer now here and a couple of other things

 On my last payday I purchased a 3D printer, specifically an Ender 3 Pro which I ordered with a suitable amount of filament to get going, though it came with some filament anyway but only a small amount compared to what I ordered, in both Amateur and CB radio circles a 3D printer is very useful indeed as you can 3D print things like antenna parts and other useful things, one of my first designs was an adaptor to allow my 7-meter SOTApole to sit in my drive on mast stand, I also had a look on Thingiverse and found some SO239 cover caps which are ideal for my radios that are on the display shelves in the shack, though do consider that these radios do get put on air from time to time.

The prior payday I ordered in some Motorola T62 PMR446 handhelds, these seem to work ok and I did a video on the YouTube channel about these, they meet the newer spec of allowing 16 channels here in the UK however that needs activating as they are 8 channel by default.

I also ordered a TinySA which I have yet to finish the video on, and an antenna from Wish that is designed for CB handhelds and is telescopic, which I will be pitting against the Albrecht CL27, the stock antennas on both modern handhelds and the comparable antenna found on my 1980s Realistic TRC-1007, it also came with a magmount so I'll be putting it on the car roof and connecting it to a radio and an analyser to see how it fairs in that regard.

I also hope to look at the new Thunderpole T-600, which I have seen pictures of and know full well who makes it, I already own the PNI Escort HP7120, which is electronically the same radio, but the T-600 appears to use different firmware to allow AM/FM switching on the CEPT channels while in the UK mode, this will possibly be featured after my next payday.

I'll also try and update this more as like everything I have been doing it has been disrupted by a hectic work schedule

73 de M0WNU/26CT730

After many years it may be I get a go in the 144MHz FMAC after all

 So it has taken a few years now however luck has it that on Tuesday I will not be working and therefore can take part in the 2-meter FM activity contest after all, this is of course subject to a lot of things, but I will not be changing job, moving house, or suffering clutch failure on the car (the clutch was changed in November due to bearing failure).

I have logging software on my Hi10 Air tablet ready to go and just need to set up the log for the day, filming will be taking place for YouTube and will be on the channel afterwards so you can see how I got on.

Antenna wise I hope to use my tape measure Yagi, radio will be the FTM-400XDE unless for some reason that is not possible in which case I'll use the FT2D handheld which will make me a QRP station in that case however there is some gain on the antenna which may help should the FT2D be needed, I will also be putting a bulletin of my participation on the contest onto APRS earlier in the day.

As every other time I've wanted to do this contest something has gone wrong I have missed out a lot, this is my first go at a contest if it happens and even though I know full well I will never win it at least I can say I've done it.

looking forward to doing well.

73 de M0WNU

There be pirates Cap'n transmitting SSTV on 27.700 MHz USB rendering UK CB channel 11 unusable

 Yesterday before work I noticed the conditions down on 11-meters (and presumably 10) were good, tuning to UK channel 11, as you'll see in the attached video clip, I heard SSTV transmitted using USB, which is illegal to do outside of the normal CB frequency range and also on 27/81 which is strictly UK use and FM only (no laws state SSTV cannot be used on CB at all however that I know of), naturally pirate operators generally do not care until the authorities actually catch them, at which point the pirate operator is stripped of all equipment and prosecuted.

So while CB does have its uses, in the UK it is authorised as licence-exempt non-interference non-protected, in short you cannot cause interference to others and you cannot report interference as no action will be taken, so these European pirates sadly will stop channel 11 in the UK from working until they realise this channel is active using FM all the time in the UK.

73 de M0WNU/26CT730

Beginner's guide to CB radio videos now live on YouTube

So I finished up with the beginner's guide to CB radio videos on YouTube the other day and got them all batch-uploaded to YouTube, each covering a different subject, I would have liked to do a demonstration of installation in a vehicle but as I don't have a vehicle to do an install in at the moment I can't obviously do this right now but once I get a vehicle I can do this I will do a demonstration of this.

In the mean time here is the playlist so far

If you are new to radio communications and need an effective useful radio setup CB radio is your answer, these work where mobile phones do not so if you are in a group in separate cars you can keep in touch, legally while driving too.

73 de M0WNU/26CT730 (or just the red squirrel will suffice on CB)