Mobile radio advice

[timsabre]

More on Baofeng.

 

I've got 6 on my desk as their chargers have been failed by PAT company. Yup - crap, hair thin, single insulated cables from wall-wart to cradle, and 13A fuses. Fixable, but definitely NOT compliment with anything.

 

?? isn't that on the low voltage side?

[Andrew C]

isn't that on the low voltage side?

Sorry, I had a wall wart in as well. No, the Baofeng has a plug (not moulded) a cr@p cable, and a cradle with the charging circuit in it.

[abbotsmike]

Would that be the bf888 or similar per chance?

 

I bought some to play with, one of the chargers died in a horrible smoky manner not long afterwards!

[Andrew C]

Don't know. Gone back to the theatre, I'll check.

[TomHoward]

I believe it's the same, we have the Pofung GT-1 and our housekeeping dept have some BF888s and both have 13A plugs with mains bell wire going into the base, with all the electronics in the base.

[paulears]

Some of the Motorola chargers have the same kind of cable, I can see the sense in a way, because the charger pod is so light, stiff cable would move it!

[Andrew C]

SINGLE INSULATED bell wire. Plug top labelled "3A Fuse" fitted with a shaky looking thing labelled "13A" .

 

Unless of course these were knock-off Baufengs...

[Andrew C]

Would that be the bf888 or similar per chance?

They are indeed BF888s.

[paulears]

I doubt there is a knock-off Baofeng - being less than ten quid now. Joking aside - the Baofeng products are all dirt cheap, and to be honest, seem no worse reliability wise than expensive ones - apart from the fact that dropping one is often terminal because the battery guids snap off, the batteries fall off, the batteries split, the spring contacts get weak, the aerial socket on the top snaps off, the ones with displays often don't!, the audio is a bit harsh, and their resistance to interference is zero.

 

You get tons of features for a few pounds on the cleverer ones, so in a way, what do you expect for the money. If you have a Motorola or Kenwood inventory, and mix in a Baofeng into a hire, nobody notices, and some rather like the smaller size and lighter weight.

 

When a £400 radio gets returned having been dropped in the mud and then dug out, I'd rather they had used a Baofeng. It's not unknown for me to throw a few into the case for regular clients who demonstrate a less than caring approach.

 

I suspect that none of the chargers have a real CE mark - but they do at least pretend quite well.

[Andrew C]

Any PAT tester looking at them with his eyes open will fail them.

[paulears]

That's why so many never fail the PAT. The machine is God. I'm not quite sure about these mains cables - they do seem amazingly common now - just a few tiny strands of copper in fairly chunky plastic. Is the cable actually considered as circuit protection in that it fails in quite unspectacular style by the two or three strands simply melting, with no insulation damage?

 

What actually sets the cable capacity in terms of cross section? Trying to be Devil's advocate here. Two pin mains cable, and an adaptor. Proper fused one, or one of Big Clive's deathdaptors? The two core cable could be 2.5mm2, or any of the smaller sizes, depending on that power consumption in a no-fault state, or a short?

 

What do you think?

[richardash1981]

What actually sets the cable capacity in terms of cross section? Trying to be Devil's advocate here. Two pin mains cable, and an adaptor. Proper fused one, or one of Big Clive's deathdaptors? The two core cable could be 2.5mm2, or any of the smaller sizes, depending on that power consumption in a no-fault state, or a short?

Technically there are three constraints on any cable:

1. Current carrying capacity based on maximum conductor temperature under sustained load. IEC 60287 gives the calculations for this if you are feeling brave!
2. Fault current carrying capacity, calculated via the adiabatic method (assume fault is short enough no heat is lost from the cable), or non-adiabatic methods if you are pushing the envelope.
3. Mechanical robustness considerations, i.e. not falling apart in use. Examples would be the wiring regulations specifying a minimum of 2.5mm^2 for caravan hook up, and some minimum earth conductor sizes.

I would suspect that for most chargers 2 and 3 are the relevant ones, because 1 is going to give a microscopically thin conductor. Because appliances are portable and have to be safe, someone sets general rules rather than doing the designs from scratch in every case, as you have to for fixed installations.

 

I'm pretty sure that cables which melt before the fuse blows are by definition not acceptable, because it's not going to achieve the level of energy containment required to act as a protective device (the results of testing one on a short-circuit current rig with something like 16kA available would be interesting - although there probably wouldn't be much left to look at!

[ANDYLASER]

I would chose the simplest to operate ones. You users will not need keypads, menus and frequency readouts.

 

A simple rotary channel knob, volume and squelch will suffice. My choice would be.-

 

Icom IC-F4002 UHF

http://www.icomuk.co.uk/IC-F3002_&_IC-F4002/PMR_Handheld_Radio

 

Although the Kenwoods mentioned earlier would be equally suitable.

[paulears]

As usual, the original topic got a bit obscured because we got a bit carried away with the dodgy wiring on some popular radios.

 

I'm a bit into radios - and having a decent quantity that I hire out, often try things out on my own jobs, and for the last year, I've been running some linked in to a Tecpro system through a repeater - it's in TX mode all the time, and I wasn't sure about things like battery life, but that does appear to be a non-issue. I started with Kenwoods - simple ones, like you suggest - with few bells and whistles, however, a few gizmos can actually be quite handy - although I'm not sure if I was buying, I'd be looking at the Icoms, price wise. I've given everyone who is not working from a dedicated position a radio - stage left, right and flys in my case, plus myself. We're running short handed compared to previous years, so having people who can run around is working. The system of operating is that we all hear the comms line traffic, and if we want to we can press the button (remote clipped to the polo short collar) to add a radio's output to the system. What's proving handy is having the radios sending out their ID, and entering a look up table so that when any radio transmits, the others show "PAUL" on the display. Even though the DSM has a proper headset, she also can look at her radio's display. So we're using it as a kind of acknowledgment system, with the DSM saying whilst talking - did you get that Paul, and a quick blip of the PTT puts my name up. The radios are also digital types, so I've set them up with a couple of digital channels too for one to one working. Oddly, Kenwood NXDN seems to work pretty well interference wise, DMR in Tier1 is much more unfriendly and leak into less well screened kit.

 

With quite a lot of different radio kit in stock, one thing is very clear - audio quality on transmite and receive is VERY different, brand to brand, and even between models. I have Motorola, Icom, Kenwood and quite a few different Chinese products on the shelf, and with a coiled speaker tube into an ear-bud, some are quite unpleasant to listen to - especially when turned up. Motorola and the Chinese ones are brightest, the Icoms quite neutral, and the Kenwoods more mellow in general. DMR and the NXDN are quite difficult to hear when the volume on stage is high - the companders mangle the audio quite badly - I think the DMR and Chinese dPMR radios are the most understandable, and my favourites, the Kenwood NXND have difficulty because they're a bit too mellow with the slightly robotic sound. They're fine outside, on their speaker, just tricky with the earpieces.

 

I know we've done this a few times before - but ALL the tecpro call button systems, and the vox radios are simply unacceptable for show use in my humble opinion. I know people use them and find them fine, but I cannot stand the unreliability of vox when it refuses to activate because the ambient noise is too high, or activates when you don't want it to, and even when it works well, it still chops the start off. Remote mics with PTT and earpiece are workable - but if you have a mix of cabled and wireless, everyone losing the DSM when somebody transmits is horrible. Digital duplex is still extremely expensive, so walkie talkies still have a place - but you need to try them out to see if they work for what you do. From time to time, even the silly LED torch in some of the cheap Boafengs really does come in handy! You could have ten Baofengs for less than one Icom, and if you drop one off the fly floor, I guess that can be lived with. Even a second hand repeater can be got for around £400, which with a £75 licence and a bit of antenna fiddling isn't a bad price for a working comms system - if you want to go totally radio - costs a bit more to get it working with a cabled system of course, unless you have a spare comms pack laying around. The options are varied and many quite workable.