Hi,

I need some help from the transistor radio experts out there.

I volunteered (don't get paid) to repair radios for the Radio Reading Services
in Cincinnati, Ohio. These radios are used by blind people to receive local
information that is transmitted as an SCA signal by educational station WGUC on 90.9 FM.

I would be interested in any service information for the radio made by a
Chinese company called "Success model ML-922" or model "HL-922".

Many of the radios I have received of this model are missing some or all of
the screws that secure the back case to the front.

I have included a picture of the screw and one of the radios.

I need help with a technical description of the screw (eg. 4-40 x 2" philips head)
that I need so that I can search eBay and various companies for pricing.
The metric screw dimensions are 30mm length, thread width about 2.85mm, and
head is a Philips with width about 4.8mm.

I spent some time on the internet trying to figure out the specs for the
type of screw I need but didn't make much progress. It kinda appears to
be something like a 3mm x 30mm pan head, but how is the taper defined?
It is certainly not a machine screw as it screws into plastic.

If you know how to specify the screw and perhaps some suggestions where to buy
I would be grateful.

I tried a google search on the company and model but didn't find anything.



Thanks for reading this.


Jack, WB8BFS

This may be what you are looking for.
(link) http://www.mcmaster.com/#tapping-screws/=mt43gg
http://www.mcmaster.com/#tapping-screws/=mt43ry
http://www.mcmaster.com/#tapping-screws/=mt44lg

Bills,

Thanks for the info. I tried McMaster-Carr earlier today (same page actually)
but all their stuff appears to be non metric and they don't have the length
that I need.

Thanks,

Jack

Hi Jack,

Referring to this as a 4-40 is a misnomer. -- That would indicate it is a machine screw.
I've always seen them called 'sheet metal' screws.

Is there a Mom & Pop hardware store close by?
The big box stores won't have the expertise to find what you're looking for,
but the smaller ones with an old-timer can probably help.

I'll poke around my junk box and see if I have a few that are close.

~ Mitch ~

Mitch,

Thanks for the reply. I am planning to go to one of the Hobby shops to see if they
might be able to help. When I quoted the (4-40 x 2") I was trying to express that I
need to know the size of the screw in the picture, I only used 4-40 as an example.
I believe it to be metric but don't know what the description (xx by xx by xx) is of
the screw in the picture.

Bill's post about McMaster-Carr shows screws intended to be used with plastic but their
screws are not metric and are not long enough.

Thanks,

Jack

If you check the links I posted you will indeed see that they have metric.
scroll down and you will see

Bill,

You are correct.... Guess I did not scroll down far enough.
Unfortunately the screws they have are a max of 14mm and I
need 30mm, but now I know the screw size and thread is
M2.63 x 1.06.

Thanks for the help.

Jack