Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Hum with phonograph only??
#1

   
6/2/13
Done restoring a 53-1750 Radio/Phono console. Replaced ALL caps and most resistors. I also replaced the cap underneath the phonograph where all the guts are. When I turn the selector knob to phono, I get a pretty good buzz which is not present on the radio band(s). Gets even worse when I put my hand near the needle arm. It does play the records fine (also put in new belt and idler wheel) --but has this background buzz/hum while in phono mode. Maybe it's just interference being picked up from electric devices in the house?? Not sure. Any ideas??
Thanks,
Mike
#2

Grounding. Check your wires from the adapter, the shield and whether the chassis is connected to the radio's chassis and how.

I do not know how it should be (I have no sch) but this is typicsally the reason - the Grounds and Ground loops.

meantime you can describe how the turn table is connected to the radio. In all details.
#3

Hi Od
Do you have to turn up the phonograph pretty loud to hear it?? Short of a ground loop you may have a weak cartridge.
Terry
#4

As far as I can tell, there are no grounding problems. Everything is connected and I've check all the new caps to make sure connections are solid.

As far as turning up the volume to hear the record better -- I would have to say yes. I probably due to have to give it some power to hear it better.
It does have a brand new needle but the cartridge is the old one. When I put my hand near the cartridge/needle, the humming gets louder.

I'm not sure if the cartridges are readily available for this 53-1750. I would have to check.

Mike
#5

Sure sounds like the tone arm and/or cartridge body are not grounded.
Corrosion in cart mounting screws, tone arm pivots?? Missing ground wire
from tone arm down thru the "hole" to turntable frame?

Just typing out loud...

Chuck
#6

I also think so. Well-grounded adaptors should not produce hum even at large volume setting. Especially if you move your hand close to it.

PS. I do not know much about those but...by chance, they did not rely on the shield being also the GND signal conductor, did they? That would not be good.
#7

6/4/13 Thanks people -- OK I will look more closely at the needle cartridge and arm and grounding wires. I'll have to unscrew the phonograph and take it back out . What a pain in the neck !! It's very hard to get access to the arm while the phongraph is installed in the draw. Also, looks like EV (Electrovoice) makes a repro cartridge for this phonograph.
Cheers,
Mike
#8

I concur with the rest of the comments. Double check the tonearm and cartridge ground before spending money on a new cartridge. Nothing worse than dropping money just to find out it didn't cure a thing. Take care. Gary

"Don't pity the dead, pity the living, above all, those living without love."
Professor Albus Dumbledore
Gary - Westland Michigan
#9

Work backwards or fowards if you prefer shorting (1st grid) or audio signal only from the volume control backwards to the cartridge. Wherever you wind up, it's the trouble point. Just don't short out any B+ voltages.

Best guess 1. bad cartridge, 2. bad shield. Pray for #2.




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
trying to identify this wire type
Thanks to all for the feedback. As Arran said, it is probably an older replacement and yes it has a grid cap so I will ...georgetownjohn — 09:32 PM
trying to identify this wire type
It's possible that the red wire, actually a grid cap lead, is a very old replacement, I can't remember seeing a pre 1939...Arran — 09:18 PM
Gilfillan Brothers Car Radio?
Hi everyone,  Special thanks to Joe Rossi for tracking down this obscure radio and thanks to others who took up the hun...Antipodal — 08:15 PM
trying to identify this wire type
Here's one source for your wire of many. Take care and BE HEALTHY! Gary P.S. Can't get the right color you need? I ...GarySP — 06:40 PM
trying to identify this wire type
...and modern wire of the appropriate gauges and insulation V-rating (300V minimum, usually shown right on the wire) is ...morzh — 05:47 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
I have a question about this radio, is there anyone that has access to this radio that has an intact unmolested speaker ...captainclock1988 — 04:28 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
Well what makes me confuse all of those companies is that all three of those companies (Setchell-Carlson, Stromberg-Carl...captainclock1988 — 04:21 PM
trying to identify this wire type
The red wire is rubber covered wire. The others are cotton braid over rubber often in colors or a tracer, also strand...Chas — 02:43 PM
trying to identify this wire type
Greetings Phorum members, Hope you can help me identify this type of wire in the photo I have attached.  I am not sure ...georgetownjohn — 01:53 PM
Philco 60 Squealing
All correct shields must be in place, all tubes correct no subs of any kind. Check any soldered, riveted ground conne...Chas — 01:24 PM

[-]
Who's Online
There are currently 5121 online users. [Complete List]
» 1 Member(s) | 5120 Guest(s)
Avatar

>