DAB aerial revisited

[Bill]

Thanks for the replies to my previous question about replacing a DAB aerial on a kitchen radio. I was going to make a small ground plane with a 13" vertical rod through it, and had located the wire coat hanger, cardboard and silver paper (mmmm chocolate) and the epoxy to assemble it all.

I then dismantled the radio, freed off the connector and checked everything out only to discover that there was an intermittent break in the short piece of thin coax from the pcb to the aerial socket. This break was not visible - an inch or so down inside the cable.

Replaced the cable, put the broken telescopic aerial back on, extended it to just under 10" vertically and it now works with only the occasional burble.

SWMBO is happy, and I'm only slightly embarrassed, as the break only became really apparent when the coax was flexed with the radio on after I'd noticed how the inner seemed to move more than the outer. I suspect the cable has been faulty since the set was new.

[Paul D Smith]

If I had a quid for every time I'd planned a fix, only to discover only something minor was wrong when I opened it up ...

Not really your fault that the cable is poor. Out of interest, what sort of cable was it? Coax? Straight forward bit-o-copper?

Paul DS.

[Brian Gaff]

Well if it was a cheap ex return, I suspect it could have been done when the module was replaced perhaps. They never fixed them, just checked and put in a new one.

Brian

[Bill]

In message , Paul D Smith writes

It was thin screened cable, not coax as I know it. I actually replaced it with something vaguely similar from the shed. It had to be quite flexible to allow the works of the radio to be taken in and out of the box.

And Brian, It was a Pure Evoke unit badged as Classic FM, and bought from some offer years ago in Boots. It wasn't sold as refurbished.

[Bill Wright]

A common problem with miniature coax, if it is flexed much. We had a run of hospital TV where the coax was 3mm stuff running through the wall bracket arm, stressed at each elbow.

Bill

[The Natural Philosopher]

It wouldn't be the first...

In my time 'doing electronics' its surprising how many times you find a fault and scratch your bum and think. 'there was no way that happened post assembly, it must have always been that way'.

[tony sayer]

I have heard that some of the Pure range haven't been that good a performer and some DAD and FM sets have a bit to be desired on FM let alone the missing "bits" on DAB!.....

[Paul D Smith]

Sounds like the stuff commonly found inside WiFi boxes; these normally have a board with the transmitter/receiver attached to the antenna with a short length of this stuff. Pretty stiff and inflexible but I've yet to come across one that was broken. I have a couple spare because I replace the "fixed" antenna on mine with a suitable screw terminal as the ADSL router is in the worst possible place for WiFi coverage. I then have some good coax to a remotely placed antenna. The antenna is only about 9 feet away but this makes the difference between OK coverage and no coverage in most of my house.

Paul DS.

[The Natural Philosopher]

Bit suspect that. Wifi is 2.4GHz, DAB is a couple of hundred MHz

Dab should go down TV coax OK but wifi wont.