Testing a cartridge to see if it works

[timmy1]

I ordered a volume control for the recordette I am working but I also found a machine that has 3 speeds but playback is untested. Is there a way I can check my needle cartridge with a ome meter to see if it is going to work before I get the machine.

[Steve E.]

Is the cartridge on the machine?

[timmy1]

No I have a cartridge out of the machine the machine did not come in the mail yet.

[tragwag]

im not positive, but I think the condition of the cartridge for a recordette has to do with the crystal inside.
I believe thats a different process than testing a magnetic cutting head.

[Angus McCarthy]

If I recall correctly, the crystal heads had a fairly high impedance - in the range of 500 ohms. I'm not sure whether it would read any differently whether the crystal has dried out or not.

[markrob]

Hi,

The crystal heads are typically much higher impedance and not easily measured with an ohmmeter. One possible way to check would be to attach the head to the input of a high impedance audio amplifier (10K ohms or greater) and lightly tap the stylus to see if any voltage is generated. The head should act like a microphone and produce some sound in the speaker. I'm gusseing the head will be dead. The Rochelle salt crystals used in these type heads are known to deterorate over time. Very few survive this long. Even new old stock units are typically dead. One possible solution is to find an Astatic M41 head. These were magnetic and were often used as replacments for crystal heads. The documentation for the M41 even shows how to modify the circut of the typical home recorder to accomodate them. It amounts to changing the head connection from the audio output plate to the speaker (after the outpit transformer). The only downside is that in the case of the Recordio, you would loose the playback ability as the cutter head was used for both functions. That's not a big deal in my book.

Mark

[timmy1]

Hi,

The crystal heads are typically much higher impedance and not easily measured with an ohmmeter. One possible way to check would be to attach the head to the input of a high impedance audio amplifier (10K ohms or greater) and lightly tap the stylus to see if any voltage is generated. The head should act like a microphone and produce some sound in the speaker. I'm gusseing the head will be dead. The Rochelle salt crystals used in these type heads are known to deterorate over time. Very few survive this long. Even new old stock units are typically dead. One possible solution is to find an Astatic M41 head. These were magnetic and were often used as replacments for crystal heads. The documentation for the M41 even shows how to modify the circut of the typical home recorder to accomodate them. It amounts to changing the head connection from the audio output plate to the speaker (after the outpit transformer). The only downside is that in the case of the Recordio, you would loose the playback ability as the cutter head was used for both functions. That's not a big deal in my book.

Mark

I finally got the amp working on my 3 speed recordette and going to try and rebuild the cartridge here is a site that explains.
http://www.angelfire.com/electronic2/radiosean/tv/Cartridge-rebuild.htm
and
http://www.philcoradio.com/phorum/showthread.php?tid=1019

[timmy1]

A friend and I cut a piece of piazo and inserted it between the old crystal holder in the slot and we got sound on a record but it was very low. We insulated the insides of the cartridge with pieces of a thin rubber glover wrapped around it.

[timmy1]

On a Shure W56N cartridge what is supposed to hold the needle holder to the u piece that the crystal slides in to thanks.

[timmy1]

I bought a radio shack piezo 273-073 and I talked to Ben on the iphone using facetime and after i put it in the cartridge the sound was very low. Ben is looking in to trying a different piazo

[Steve E.]

We really need more people who can fix crystal heads.

[opcode66]

I think I'll be able to offer mono repairs on magnetic heads within another three or four months. Things are moving along well so far.

[45rpmdude]

Been there done that,, Those only work for the player end. but try anyways..

[morrisjer]

Hi Lathe guys,

This is Jerry here. I am the seller of the cutting needles on ebay for $10 and the Tungsten ones for $15. I have done well in the year and half of sales. However, I have other cutters that need cartridge replacement (old crystal cartridges). I had one replaced about a year or so ago by West Tech and it was great--still works. That was for my Recordio. However, I also have a Ultratone by Audio Industries and a Wilcox-Gay 3 speed cutter. The Ultratone is a large X-26 crystal cartridge, and I learned it could cost $75 to rebuild. I looked on the Internet and found some sites that showed HOW to rebuild crystal cartridges. I was sort of timid to try to rebuild so I put it back into my mind. Then I bought an X-26 rebuilt cartridge on ebay and it did not work! I got brave and opened it and I never saw such JB Weld put here and there in my life! That is when I pulled the X-26 cartridge from my Ultratone and opened it. Naturally, the crystals had disintegrated. I went and bought a Piezo element and went through all the steps to rebuild. I loved it! I hooked it up to an extention speaker in my Califone player and could hear the cartridge reproduce the sound great! NOW, I want to rebuild all my other cartridges and may perhaps in the future wish to rebuild for others. Hit me up for some encouragement, I may be doing this also in the future.

Jerry

[timmy1]

Hi Lathe guys,

This is Jerry here. I am the seller of the cutting needles on ebay for $10 and the Tungsten ones for $15. I have done well in the year and half of sales. However, I have other cutters that need cartridge replacement (old crystal cartridges). I had one replaced about a year or so ago by West Tech and it was great--still works. That was for my Recordio. However, I also have a Ultratone by Audio Industries and a Wilcox-Gay 3 speed cutter. The Ultratone is a large X-26 crystal cartridge, and I learned it could cost $75 to rebuild. I looked on the Internet and found some sites that showed HOW to rebuild crystal cartridges. I was sort of timid to try to rebuild so I put it back into my mind. Then I bought an X-26 rebuilt cartridge on ebay and it did not work! I got brave and opened it and I never saw such JB Weld put here and there in my life! That is when I pulled the X-26 cartridge from my Ultratone and opened it. Naturally, the crystals had disintegrated. I went and bought a Piezo element and went through all the steps to rebuild. I loved it! I hooked it up to an extention speaker in my Califone player and could hear the cartridge reproduce the sound great! NOW, I want to rebuild all my other cartridges and may perhaps in the future wish to rebuild for others. Hit me up for some encouragement, I may be doing this also in the future.

Jerry

I tried it once I bought a piezo from radio shack but the cartridge was not too loud was yours loud?

[morrisjer]

I was going by what I heard when I put my ear near the X-26 cartridge after rebuild. I had a line from my Califone extension speaker (8 ohms 10 watts) to the cartridge when I played a record. I heard the record ok. I just had masking tape around the cartridge just to test, but now I will have to put rivets (perhaps split rivets) to seal the cartridge and go through the process of putting it back in the cutting arm. There are springs that will have to be connected as this type of cartridge uses them for the depth of cut mechanism. Perhaps this extension speaker output wasn't the right medium to use for a test and I will find out later (hopefully not a problem). In any event, if the Radio Shack Piezo isn't all its cracked up to be, what type should I buy? Did I test with the right ohms?

???
Jerry

[morrisjer]

NEVER did I ever think in a thousand years I would have trouble finding a rivet to secure my X-26 rebuilt cartridge back together!!!!!! Pure hell!
I went to Lowe's, Williams Electric (my area supplier) and Shields Electronics (another area supplier since Radio Shack closed). No one knew what in the hell I was talking about! I went online:

1. Jiffy Rivets (just tap the two sides together)

2. Tubular Rivets (these have a "cincher" that makes a star split on the other side)

3. Screw Post Rivets (or binding post screws) These seem to be the best???

HellP

Jerry

[venusloungerecords]

Cool tips! How do you open the x 26, I tried and was not able to do so.

[morrisjer]

That has been a while since I have done this. You may have to drill out the rivets.