Stone Dead JB7

[davco...@hotmail.com]

Hi,

I promise I searched before mkaing my first submission, but found nowt :-) 

I just passed my 70th birthday, and got my JB7 for my 60th, so I can't grumble.  I haven't used it much in recent times, well for six months at least during which time it has been happily sitting on my desk.

Having lost the power supply a couple of years ago, I purchased a replacement from Amazon which worked fine, though the connector seemed a bit loose in the socket.  Went to try it again and it's dead.  Nothing wrong with the power supply as far as I can tell, definitely not plug or fuse, which I have changed.  When I plug it in, the light on the supply doesn't go on, but I'm not sure that indicates anything wrong.  It doesn't light when plugged in without connecting to the Brennan either.

We live in rural Scotland, and the nearest shop that might help is 30+ miles away, so I thought I'd check first and see if anyone has any hints as to what else I might try?

Thanks in advance

David

[JAC]

Hi

There are two main ways of arranging the pilot light on a modern power supply.  One way is that the light indicates a DC output present, irrespective of whether any current is being drawn.  The other way (less common) is that the light only comes on when a load is connected and drawing current.  In either case, given that the lights are LEDs and pretty reliable, no light with JB7 connected would seem to indicate that the power supply has developed a fault.  Are you able to put a test meter on the DC output lead plug ? Or even a couple of car indicator bulbs in series, which will draw a couple of amps and light up ?

The other point to watch is that the DC connectors with a concentric inner and outer part don't seem to be standardised very well in their dimensions.  You need both inner and outer sizes to be right.  You also need some sort of springiness for a good connection, such as a forked blade for the female inner.  If you are unlucky, its possible to end up with an un-springy pin mated with an un-springy hole.  It fits OK but the connection is unreliable.  Sometimes plugging and unplugging a few times and twisting a bit will wear off any tarnish, so that's another simple thing to try.

[PMB]

Hi David,

If the led on the power supply isn't lighting up I would suspect a fault with the power supply.

The correct DC connector has a 5.5mm outer diameter and accepts a 2.1mm pin. The centre contact is +ve i.e. +24V.  

Paul

Brennan Support.

[davco...@hotmail.com]

Thanks for the quick replies.  I think the power supply is kaput as there's no light, but it might be the connector which has very little resistance when being pulled in and out.  Nothing's happened between it working and not working though!  Pukka power supply is a bit expensive and, I assume, is subject to the springy thingy anyway.  Maybe I should treat myself to the latest model.  Ho hum... bite the bullet and try the shop I think, unless somebody comes up with another idea.  

Thanks!

David

[fred.w....@gmail.com]

Hi David, do this logically in small steps, cheapest first, then going down more costly.

1) I think that the first step would be to try another power supply  (Paul has told you what you need "The correct DC connector has a 5.5mm outer diameter and accepts a 2.1mm pin. The centre contact is +ve i.e. +24V.  ")

eg https://www.amazon.co.uk/Adapter-Switching-Connector-Computer-Monitor-24V-2-5A-AC-11-DC-JACK/dp/B07S5QG3LH/ref=psdc_1345746031_t1_B07GFBYKGD

This may sort you out.

2) If NOT I believe you can get a JB7 repaired by 

https://www.facebook.com/audiotech2017/?ti=as

3) You could also get a new Brennan B2 unit (or a BB1) from Brennan at

https://www.brennan.co.uk/units

-----------------

I do not know how much Music you have on your JB7 but if it is a lot (and you want a new Brennan) then getting your JB7 up and running will enable you to export your music from that and (then) import it into your new Brennan. This would save a lot of loading of CDs etc.

Hope this helps.

Fred

[davco...@hotmail.com]

Thanks for that Fred, but shelling out another twenty quid for a power supply that might not be of any use isn't my preferred first step!  Since last writing, I've phoned the Euronics shop and as I'm making the 70 mile round trip into town tomorrow, they will be able to at least say where the problem is. Happily, I have a backup of my music, but I would rip it again if I bought a new machine as the quality versus storage question has changed. 

I do like the idea of the new machine, and given that we have two very large purpose-built cupboards housing our CDs and DVDs, maybe the time has come to ditch physical and pray nobody starts slinging EMPs around any time soon!

Cheers

David

[fred.w....@gmail.com]

Well David,

Reading what you have just said - It seems to me that you want a new B2 anyway and want to reload all your data anyway! So stop worrying about your JB7 and write that letter to Santa right away! :))

Fred

[davco...@hotmail.com]

If only life were that simple ;-)  Gone are the days when I could buy gizmos on a whim.  Not just because I always consult She Who Must At Least Believe She's Being Obeyed, but I've wasted enough over the years.  

Cheers

David

[fred.w....@gmail.com]

You will have to convince Mrs Claws that you haven't been naughty and that she needs that cupboard space where all the CDs are now ;))

Frd

[PMB]

Hi David,

If Euronics don't have a 24V supply, a 19V (typical laptop supply) with the correct connector and polarity could be used to test the JB7 (at least to check it powers up). I think 15V may be enough but haven't tried that.....

Paul

Brennan Support.

[davco...@hotmail.com]

Thanks Paul.  I dropped it off with them this morning, hoping they would have a look at it so thatmy wife could pick it up when she goes into town tomorrow (it's a 70 mile round trip).  I reckoned without Covid, so it has to sit in the corner for a few days before they can look at it.

Cheers

David

[PMB]

Hi David,

OK let us know how it goes.

Paul

Brennan Support.