The concept addresses and seems to solve many new (old radio) owner's problems

Most folks like to hear big band or old-time music on these radios but not only does nobody broadcast it anymore... they are usually not near good strong AM stations.

So some people revert to making their own AM transmitters and listening that way.

Some folks want FM too.

... The Ipod aux jack takes care of all these desires.

I own a little Sansa-Clip brand Ipod-clone from Radio-Shack that I got for only $40 or so.
It holds up to 500 tunes and has an FM radio built in.

So I decided to start adding an AUX jack like this to some of my radios, especially those with nice audio amp sections like my current Silvertone model-1962 with a 6F6 PP amp.

Here is a picture of the Radio-Shack stereo jack that I'm using.

Radio-Shack #274-0246
http://www.radioshack.com/product/index.jsp?productId=2103451&tab=summary

I tried it out the other night here on this Silvertone I have on my bench now:
http://www.nostalgiaair.org/Resources/861/M0016861.htm

I made a few tack-solder connections leaving the jack itself hanging out in the air while I was testing.
When I plugged in my Sans-Clip audio signal the most beautiful music came through the Silvertone as anticipated.

However all was NOT to remain blissful very long.

The first consideration for connection was to lift the the top of the volume control and and feed that into and back out of my "normally/closed" AUX jack contacts.

It did work but I didn't seem to be able to get the volume I wanted.

I guess the 500k pot was too much load.

So instead I lifted the wiper lead from the vol pot that feeds the .05 cap to the first audio tube.
So I fed my AUX input in there to the .05uf cap right where it was disconnected from the wiper lead.

......with the input signal ground reference connected to the low end of the vol pot.... ( the cathode of the 6Q7 1st audio tube)

This seems to work fine.

I am not sure though if I am providing the proper load for the AUX device's output. ( It normally looks at earphones as the load)
And of course... the volume must now be controlled from the Aux device.

The first actual "problems" showed up when I decided to clean up my rat's nest of test wires and install the jack permanently by drilling a hole in the rear of the chassis and attaching it there.

When I fired it up.. I had some serious HUM.

So I carefully re-routed all my leads with shielded audio cables everywhere. But I still had some hum.

I thought that maybe my audio cable from the Sansa-Clip (Ipod-clone) source was not shielded... so I went to RadioShack and bought a couple of properly shielded cables.

However there was no improvement.

Then I put on my thinking cap... and the 'light' went on in my wittle brain...lol

As I examined the schematic I realized that the low end of the vol pot is at -1.2 vdc... NOT chassis ground... AH HA!

This was at first no great problem to me I thought,.. "I'll just wire it to that point."

Yeah.. ok.. BUT then how am I going to be able to properly MOUNT this jack without physically screwing it to the chassis forcing the input signal ground to become chassis ground and screwing up the 6Q7's cathode reference of -1.2 volts??

OMG... what to do?

Well in this particular case I fashioned a 'Rube Goldberg" solution by making an enlarged hole in the metal chassis and affixing an insulator of clear plastic on the inside and another on the outside. Then making a smaller hole in the center of the plastic to mount the AUX jack.
If I had access to a hole punch and some phenolic wafer material I could mount the phenolic wafer on the chassis and then mount the AUX jack on that.

So this works alright .... but NOW the outside mounting hardware of the AUX jack is at -1.2 volts below the surrounding metal chassis.

And for the future I will have to consider each radio on a case-by-case basis.

Many old radios like this one do not have the audio section referenced to chassis ground.

And as far as an AA5 transformer-less radio goes...
I will have GREAT considerations.

First make sure I use a polarized AC plug.
... and make sure that the neutral side is ALWAYS connected to the metal chassis.

But here again.. If the AA5 uses a floating ground I will have to "float" the AuX jack hardware too.... otherwise I will be defeating the "floating' ground.

So this is all kinda interesting. No?

So what do you guys think?
.. and what kind of ideas do you think would be clever to be able to both "isolate' the AUX input ground as well as finding a nice simple insulated method of attachment.

I was thinking that many AA5 radios with loop antennas have room on the back panel cardboard to mount the jack... but with a lot of in/out jacking it may weaken the cardboard.

Any thoughts?

marv

:I have recently seen a few nice old radios selling on Ebay that sport the currently-popular, often requested, "Ipod-type" aux input jack.
:
:The concept addresses and seems to solve many new (old radio) owner's problems
:
:Most folks like to hear big band or old-time music on these radios but not only does nobody broadcast it anymore... they are usually not near good strong AM stations.
:
:So some people revert to making their own AM transmitters and listening that way.
:
:Some folks want FM too.
:
:... The Ipod aux jack takes care of all these desires.
:
:I own a little Sansa-Clip brand Ipod-clone from Radio-Shack that I got for only $40 or so.
:It holds up to 500 tunes and has an FM radio built in.
:
:So I decided to start adding an AUX jack like this to some of my radios, especially those with nice audio amp sections like my current Silvertone model-1962 with a 6F6 PP amp.
:
:Here is a picture of the Radio-Shack stereo jack that I'm using.
:
:Radio-Shack #274-0246
:http://www.radioshack.com/product/index.jsp?productId=2103451&tab=summary
:
:
:I tried it out the other night here on this Silvertone I have on my bench now:
:http://www.nostalgiaair.org/Resources/861/M0016861.htm
:
:I made a few tack-solder connections leaving the jack itself hanging out in the air while I was testing.
:When I plugged in my Sans-Clip audio signal the most beautiful music came through the Silvertone as anticipated.
:
:However all was NOT to remain blissful very long.
:
:The first consideration for connection was to lift the the top of the volume control and and feed that into and back out of my "normally/closed" AUX jack contacts.
:
:It did work but I didn't seem to be able to get the volume I wanted.
:
:I guess the 500k pot was too much load.
:
:So instead I lifted the wiper lead from the vol pot that feeds the .05 cap to the first audio tube.
:So I fed my AUX input in there to the .05uf cap right where it was disconnected from the wiper lead.
:
: ......with the input signal ground reference connected to the low end of the vol pot.... ( the cathode of the 6Q7 1st audio tube)
:
:This seems to work fine.
:
: I am not sure though if I am providing the proper load for the AUX device's output. ( It normally looks at earphones as the load)
:And of course... the volume must now be controlled from the Aux device.
:
:The first actual "problems" showed up when I decided to clean up my rat's nest of test wires and install the jack permanently by drilling a hole in the rear of the chassis and attaching it there.
:
:When I fired it up.. I had some serious HUM.
:
:So I carefully re-routed all my leads with shielded audio cables everywhere. But I still had some hum.
:
:I thought that maybe my audio cable from the Sansa-Clip (Ipod-clone) source was not shielded... so I went to RadioShack and bought a couple of properly shielded cables.
:
:However there was no improvement.
:
:Then I put on my thinking cap... and the 'light' went on in my wittle brain...lol
:
:As I examined the schematic I realized that the low end of the vol pot is at -1.2 vdc... NOT chassis ground... AH HA!
:
:This was at first no great problem to me I thought,.. "I'll just wire it to that point."
:
:Yeah.. ok.. BUT then how am I going to be able to properly MOUNT this jack without physically screwing it to the chassis forcing the input signal ground to become chassis ground and screwing up the 6Q7's cathode reference of -1.2 volts??
:
:OMG... what to do?
:
:Well in this particular case I fashioned a 'Rube Goldberg" solution by making an enlarged hole in the metal chassis and affixing an insulator of clear plastic on the inside and another on the outside. Then making a smaller hole in the center of the plastic to mount the AUX jack.
:If I had access to a hole punch and some phenolic wafer material I could mount the phenolic wafer on the chassis and then mount the AUX jack on that.
:
:
:
:
:So this works alright .... but NOW the outside mounting hardware of the AUX jack is at -1.2 volts below the surrounding metal chassis.
:
:And for the future I will have to consider each radio on a case-by-case basis.
:
:Many old radios like this one do not have the audio section referenced to chassis ground.
:
:And as far as an AA5 transformer-less radio goes...
:I will have GREAT considerations.
:
:First make sure I use a polarized AC plug.
:... and make sure that the neutral side is ALWAYS connected to the metal chassis.
:
:But here again.. If the AA5 uses a floating ground I will have to "float" the AuX jack hardware too.... otherwise I will be defeating the "floating' ground.
:
:So this is all kinda interesting. No?
:
:So what do you guys think?
:.. and what kind of ideas do you think would be clever to be able to both "isolate' the AUX input ground as well as finding a nice simple insulated method of attachment.
:
:I was thinking that many AA5 radios with loop antennas have room on the back panel cardboard to mount the jack... but with a lot of in/out jacking it may weaken the cardboard.
:
:Any thoughts?
:

:Peter,
:Sell AM transmitters on ebay as a side line.
:
:marv
:
::I have recently seen a few nice old radios selling on Ebay that sport the currently-popular, often requested, "Ipod-type" aux input jack.
::
::The concept addresses and seems to solve many new (old radio) owner's problems
::
::Most folks like to hear big band or old-time music on these radios but not only does nobody broadcast it anymore... they are usually not near good strong AM stations.
::
::So some people revert to making their own AM transmitters and listening that way.
::
::Some folks want FM too.
::
::... The Ipod aux jack takes care of all these desires.
::
::I own a little Sansa-Clip brand Ipod-clone from Radio-Shack that I got for only $40 or so.
::It holds up to 500 tunes and has an FM radio built in.
::
::So I decided to start adding an AUX jack like this to some of my radios, especially those with nice audio amp sections like my current Silvertone model-1962 with a 6F6 PP amp.
::
::Here is a picture of the Radio-Shack stereo jack that I'm using.
::
::Radio-Shack #274-0246
::http://www.radioshack.com/product/index.jsp?productId=2103451&tab=summary
::
::
::I tried it out the other night here on this Silvertone I have on my bench now:
::http://www.nostalgiaair.org/Resources/861/M0016861.htm
::
::I made a few tack-solder connections leaving the jack itself hanging out in the air while I was testing.
::When I plugged in my Sans-Clip audio signal the most beautiful music came through the Silvertone as anticipated.
::
::However all was NOT to remain blissful very long.
::
::The first consideration for connection was to lift the the top of the volume control and and feed that into and back out of my "normally/closed" AUX jack contacts.
::
::It did work but I didn't seem to be able to get the volume I wanted.
::
::I guess the 500k pot was too much load.
::
::So instead I lifted the wiper lead from the vol pot that feeds the .05 cap to the first audio tube.
::So I fed my AUX input in there to the .05uf cap right where it was disconnected from the wiper lead.
::
:: ......with the input signal ground reference connected to the low end of the vol pot.... ( the cathode of the 6Q7 1st audio tube)
::
::This seems to work fine.
::
:: I am not sure though if I am providing the proper load for the AUX device's output. ( It normally looks at earphones as the load)
::And of course... the volume must now be controlled from the Aux device.
::
::The first actual "problems" showed up when I decided to clean up my rat's nest of test wires and install the jack permanently by drilling a hole in the rear of the chassis and attaching it there.
::
::When I fired it up.. I had some serious HUM.
::
::So I carefully re-routed all my leads with shielded audio cables everywhere. But I still had some hum.
::
::I thought that maybe my audio cable from the Sansa-Clip (Ipod-clone) source was not shielded... so I went to RadioShack and bought a couple of properly shielded cables.
::
::However there was no improvement.
::
::Then I put on my thinking cap... and the 'light' went on in my wittle brain...lol
::
::As I examined the schematic I realized that the low end of the vol pot is at -1.2 vdc... NOT chassis ground... AH HA!
::
::This was at first no great problem to me I thought,.. "I'll just wire it to that point."
::
::Yeah.. ok.. BUT then how am I going to be able to properly MOUNT this jack without physically screwing it to the chassis forcing the input signal ground to become chassis ground and screwing up the 6Q7's cathode reference of -1.2 volts??
::
::OMG... what to do?
::
::Well in this particular case I fashioned a 'Rube Goldberg" solution by making an enlarged hole in the metal chassis and affixing an insulator of clear plastic on the inside and another on the outside. Then making a smaller hole in the center of the plastic to mount the AUX jack.
::If I had access to a hole punch and some phenolic wafer material I could mount the phenolic wafer on the chassis and then mount the AUX jack on that.
::
::
::
::
::So this works alright .... but NOW the outside mounting hardware of the AUX jack is at -1.2 volts below the surrounding metal chassis.
::
::And for the future I will have to consider each radio on a case-by-case basis.
::
::Many old radios like this one do not have the audio section referenced to chassis ground.
::
::And as far as an AA5 transformer-less radio goes...
::I will have GREAT considerations.
::
::First make sure I use a polarized AC plug.
::... and make sure that the neutral side is ALWAYS connected to the metal chassis.
::
::But here again.. If the AA5 uses a floating ground I will have to "float" the AuX jack hardware too.... otherwise I will be defeating the "floating' ground.
::
::So this is all kinda interesting. No?
::
::So what do you guys think?
::.. and what kind of ideas do you think would be clever to be able to both "isolate' the AUX input ground as well as finding a nice simple insulated method of attachment.
::
::I was thinking that many AA5 radios with loop antennas have room on the back panel cardboard to mount the jack... but with a lot of in/out jacking it may weaken the cardboard.
::
::Any thoughts?
::
:

As an experiment I disassembled what I did yesterday and ( more conventionally) fed the AUX input to the top of the vol control as is 'normally found' and .. well ... Yes ...it DOES work.. with some drawbacks.

So it seems that some songs on my Mp3 player must have different recorded levels and those "lower" ones still don't seem to generate sufficient vol.

So I left the wiring this way.. but I compromised by jumpering another .05uf cap from the top of the vol pot to the wiper. This works nicely now.

It doesn't make much if any difference when in the radio position yet it certainly allows for the lower level Mp3 tunes to be loud enough.
Of course in Aux mode the Aux vol control will be dominant vol control ...but the radio's vol control can still turn it down completely.

Peter, for what its worth Mauser has nylon and fiber "shoulder washers", measurements are in tenths of an inch but believe those would do. Kind of expensive (9-11 cents/)That tubing is cheaper and easy to cut. PL

: HI; I think this is a great idea and I have a (1930 WESTINGHOUSE WR-5) Which I think is a radiola???. maybe you could help me hook-up an r/s#274-0246 for my set. thanks chip
::
:
:Sure Chip:
:All you need to do is follow the same connections I made except try going in at the top of the vol pot instead of the wiper.
:
:

Peter, for what its worth Mauser has nylon and fiber "shoulder washers", measurements are in tenths of an inch but believe those would do. Kind of expensive (9-11 cents/)That tubing is cheaper and easy to cut. PL

: HI; I think this is a great idea and I have a (1930 WESTINGHOUSE WR-5) Which I think is a radiola???. maybe you could help me hook-up an r/s#274-0246 for my set. thanks chip
::
:
:Sure Chip:
:All you need to do is follow the same connections I made except try going in at the top of the vol pot instead of the wiper.
:
: