Western Electric 233G Noise

[Logan1]

I have a western Electric 233G and it has a buzzing noise in the reciever when it is not hooked to the wall jack and the top housing is off. It has a 685A subset hooked to it.    Any Ideas   Thanks

[Phonesrfun]

A couple more pieces of information are needed.  First of all, you had asked me about a week ago in a PM about how the coin relay was originally connected, and as part of that I mentioned that there would have been a ground connection brought in because the coin relays in the old days used a voltage between one side of the line and ground to achieve the collect and return.  If you connect a ground to the payphone that is connected to a modern line, you are likely to hear a hum when the phone is otherwise not all connected, as with the upper housing off.
So, question #1 is did you connect a ground connection that could have started the hum (buzz) noise?
Question #2, what happens when you connect it to the line and replace the upper housing?

[Logan1]

There is no ground hooked to it, it still hums with the upper housing on, I unhooked all wires to coin relay and it still hums. and it does not make any difference when I lit the reciever hook up or down.

[Logan1]

When I replace the upper housing and hook up the line I get dial tone and lower the reciver hook with my hand it still hums

[Phonesrfun]

The hum is usually indicative of one side of the line or the other touching onto something grounded, I.E. something metal.  With the pay phone hung up and/or the upper housing off, do you get the same hum in any other phone in the house?  Can you think of what activity you were doing just prior to the hum showing up?
What service do you get your dial tone from?  Legacy Phone company CO?  Internet phone?

[Logan1]

I think I might be picking up interference in the air because I unhooked every wire in the phone , no change, so I unhooked the  receiver wires completely and the noise is still there. I can hold the receiver to my head and turn my head and the noise changes. every here of that.

[twocvbloke]

In your initial post, you say it's not connected to the wall jack, so I presume it's not electrically connected to anything electrically? If so, it may be picking up mains hum from your house wiring, a few of my GPO phones did that too but I found that it was the unshielded electronic 21A transmitters known to cause mains hum, I wouldn't know where to begin to find where the issue is in your phone though, it could just be a bit of mis-wiring somewhere inside with something acting kind of like a crystal radio set playing back mains hum...

[Logan1]

I will go with that for know, just trying to make sure eveything is ok before I invest in a controller. maybe I will change the receiver and see what happens, it has a steal cable to it.  I just checked 2 other 302 phones that are not hooked up at all and they have a hum. Thanks again.

[Phonesrfun]

Without actually seeing it in person, these things can be hard to track down.  I am not at all concerned about hearing a hum if te hookswitch is down, unless the hum can also be heard in another phone connected to the same line.  It could very well be picking up inductive noise from just about anything in the room.  A flourescent light, a motor, or even just in the room in general.  When the phone is hung up, it doesn't matter.  When you go off-hook, there is a load placed on the line and all that inductive noise goes away, and is absoluetly not an issue.

However, if you get a hum on another phone in the house when the pay pone is connected to the line, then I would worry.

Remember the U1 receiver in a handset is pretty sensitive and will pick up stray noises with no other load on it.  This will never happen in a 500, since the hookswitch shunts the receiver circuit while on-hook.  The 233 opens the connection to one side of the receiver, leaving the other side connected.

You might try reversing the line L1 and L2 going to the wall and see if that makes a difference, but it probably wont.

[Phonesrfun]

Wait a second.... 2 other phones not even connected have a hum??  You must either be living under a large power line, or you have lots of flourescent lights in your house.  You don't by chance live at the power house of the Hoover Dam??

[Logan1]

I think I found the problem, I turned all the lights off in the basement and the hum goes away. must be something in the  light ballast.  Thanks

[Logan1]

It has got to be the Flourecent light I put up. Thanks, Turn them off and it is ok.  Thanks

[Phonesrfun]

You never thought you'd fix a phone problem by turning off a light, huh? 

[DavePEI]

I have had a similar situation on an Ernest based 7D1 payphone. I had it in perfect operating condition, then placed inside a boothette with lighted signs.

All of a sudden, its internally generated dial tone was gone. Finally, after much fiddling, I discovered if I turned off the fluorescent lamp in the booth, the dial tone returned. I solved the problem permanently by placing chokes in the power line to the phone, and by grinding the paint off around the mounting bolts, then re-installing the phone to improve grounding.

Yes, even conventional Fluorescents can put out a lot of RF!

For the 233 below, I would recommend installing grounding clips to improve the grounding of the upper section to the lower section. I have seen these on a few 233s - just a little metal clip which is inserted in the back groove of the phone, and which scrapes against the front panel when placed on the phone. I don't know what the proper name for  them is, or a part number. A pair of chokes on the incoming line might help, too.

Dave

[Logan1]

Good Idea,, I will try it,    Thanks