Many thanks to SWLing Post contributor, Frank Sturzaker, who writes:
I am a new SW listener in the UK and am using an elderly Sony ICF SW100E picked up from selling website here in the UK fairly cheaply as a starter. It gets excellent reviews and seems to do what is required very well. A couple of weeks ago I also picked up a non-working Sony AN-100A external antenna at a charity / thrift store here in the UK. Cheap because not working.
The antenna section simply pulled out of the plastic case so I opened it up to have a poke about inside to try to solve the problem.
The antenna has been “ripped” from however it was mounted and has taken the thin metallic shaped piece / strip that somehow connects it to the circuit board and twisted it. I would guess that this has happened when trying to rotate the extended antenna when the extending sections had become too stiff to rotate – the pieces visible from outside the unit would not rotate inside the fixed section that sits in the unit.
Photos
1 – This is what I bought (although the antenna itself was in the correct place in the case):
2 – This is a close up of the base of the antenna when first bought:
3 – The two halves of the case with the antenna in place but about 0.5″ short of where it should be:
4 – A close up of the ‘loose pieces’ from inside the case and the bottom of the antenna – on the right are the pieces that were left on the antenna and on the left is the this metal piece that makes contact with the circuit board from the antenna
5 – Photo of antenna screw hole in rear of case from inside – the broken plastic is obvious round the screw hole:
6 – Photo of underside of circuit board showing the flat metallic area where the metallic strip from the antenna makes contact:
My questions about how it all fits together (as a starter) are:
-
- Is it ONLY the screw from the outside holds the whole antenna assembly in place or is it fixed with glue etc. when originally shipped? It looks to have been ONLY the screw because there are no traces of any adhesive etc.
- Should the antenna be able to rotate at its lowest section – like on the SW100E?
- Is the thin metal strip fixed to the circuit board by anything (solder??) or does it just ‘brush against’ the metallic surface?
- If I simply fix the antenna in place with epoxy or similar and run a connector between the bottom of the antenna and the circuit board will this work or are there other things that should be done or done in a specific way?
If someone can help then great. I repeat, I am not an electronics wizard – a master with a soldering wand I am not!!!
I could go at this like a bull at a gate but advice would be appreciated if there is any out there.
Post readers: if you can offer Frank some advice, please comment. Also, if you own an AN-100E and could share some internal photos, that might help him sort out how it was originally attached inside.
Probably paid a bit too much, but I just brought home a mint SW-100S with the active antenna that is also broken loose. Seems to me that the pivoting then extended whip on axis (so it stands up straight) places undue stress on the case. There’s a lot of internal friction against this motion at the whip’s base, surely to keep it from falling down. A bit too much friction, in my view.
I will try to repair with a new, longer M2 screw to hold the antenna base in place, with a washer or small metal plate to be placed on the outside of the case. And also, I’ll add some epoxy between the antenna shaft and the base to help add support.
Finally, instead of the spring contacts, I’ve soldered a small wire from the PCB antenna pad to attach to the base of the reinforced whip, as Sony’s little metal clips/contacts don’t seem to be a permanent solution.
From what I can tell so far, this little active antenna performs pretty well to enhance the 100’s reception.
Hello all who replied. First thanks for taking the time and trouble to help. I alreqdy have a service manual (from the internet) and the small section about the antenna isn’t much help at all – I suspect that the problem I have is never intended to happen!!
The extra photos posted by Markkus help me with the box of bits that I have because I can see how it should all fit together.
I suspect that I will have another think about this and (to end up with a working antenna) simply glue to lower antenna portion to the back case where it should be screwed and put a simple copper wire soldered lead to the circuit board. This is the easy solution for me (as a non electronics person) which should work. The base of the antenna will not move (as it doesn’t in a correctly working one) but the upper part will rotate if I can loosen it and lubricate. This solution has been helped by everyone so once again thanks to all
Frank
Hi Frank,
Hope you are well, 🙂
My antenna also broken the same location, are you able to take some photos how your is done?
Thanks
Sunny
Hi Frank. There is a “groups.io” group for the Sony SW100 and in the files area is the service manual. It has the diagram for the assembly of the AN100 in it (page 40).
I can’t see how to attach a screen dump of it to this message. It looks like the telescopic antenna is only held by the screw (which in my view is not supported by much plastic!). The base of the antenna acts as a “nut” for the springy piece that extends over to the circuit board pad – just spring contact so the circuit board can be lifted away without (un)soldering.
The telescopic probably rotates but yours may be very stiff, hence the plastic broke. You can test that by gripping the base with pliers and pulling out and rotating the telescopic – spray a lubricant if necessary.
So you can reinforce the plastic area and repair the springy extension, or solder a wire, to fix it.
I opened up my AN-100.
As you thought, the little screw on the outside of the case holds the antenna in place. There is no adhesive.
The antenna does rotate at the lowest section, below the screw joint and also telescopes slightly at that point so it can clear the case when extended and the case is sat on a desk. I have photographed that section retracted and extended, in case yours doesn’t do that.
The metal strip appears to be pressed against the circuit board by the tension of bringing the two case halves together – no solder.
Photo links follow. Hope it helps.
https://ibb.co/HYjqSYD
https://ibb.co/gvFQ1z6
https://ibb.co/Y3VcMg4
https://ibb.co/GWjHQNt
Thank you for the photos, Markkus! I had the same problem as Frank and thanks to your photos I could understand what had happened and how to put it all together.
Regards.
You’re welcome 🙂
Welcome Frank,
You better get the SW-100 SM pdf from here
https://www.manualslib.com/download/383463/Sony-Icf-Sw100.html
Pages 25 & 40 are the antenna.