Exhibition Junior Question

[randymullx]

I have an Exhibition Jr. reproducer that I would like to rebuild. The closest size I can find for the mica diaphragm is 1-9/16" as used for the Concert but I'm worried it might be a shade too large. Is 1-9/16" the correct size for the Exhibition Jr? If not, does anyone have a source for the correct diaphragm? At the present time, there is no screw through the diaphragm into the foot of the needle bar.....it appears to be glued in place. Is that the correct way for it to be assembled or should there be a screw like used in the full size Exhibition? I haven't taken it completely apart yet pending info on the correct mica diaphragm as it does kind of work but sounds really bad.
Thanks for any info you can share!

[Phono-Phan]

Is the diaphragm bad? Most of the time you can just clean them. Can you post pictures? I am pretty sure there should be a screw to fasten the diaphragm to the needle bar foot. I have a couple of these Exhibition Junior reproducers and will check them to see if there is a screw for the diaphragm.

[Inigo]

Yes, the diaphragm is attached to the needle bar with a tiny screw

[Phono-Phan]

That is different than what I expected. I have the long throat Exhibition Jr. reproducers for front mount machines. Not sure what the size of the diaphragm is on yours. It looks in great shape. Are the balance springs OK on the needle bar?

[Inigo]

@Phono fan, My ex j in the photos is from a small tabletop hornless HMV Junior, with tonearm, similar to the Zonophone Cinch, so more modern, short throat.
The balance springs were broken, so I made ones from wire, installed in the EMG fashion. I removed the rests of the broken springs and used the same bolts and nuts to install the new wire springs. A reversible modification.

[randymullx]

In case it is useful to someone in the future, the answer is that the 1-9/16" diameter of the mica diaphragm for a Concert is about ⅛" too large (I estimate 1-7/16" for the correct size). I didn't get a "before" photo but the mica on mine was badly separated and was also too large as it was touching the rim (sounded VERY bad) so I had to find a solution. I was able to trim down the Concert diaphragm using a small, very sharp pair of wire cutters (Xcelite 170M in my case), taking off about 1/16" all the way around. I suggest that anyone trying this have a spare mica on-hand just in case. The reason the tiny screw into the needle bar was missing is because someone had broken it off and due to the size, I had no way to extract it or to drill and tap the hole. I didn't think beeswax would be strong enough so I ended up attaching it to the diaphragm with a couple of drops of super glue which is, at least for now, is working. The sound is dramatically improved !!

[Zwebie]

I rebuilt this Exhibition Jr. reproducer years ago, and luckily was able to re-use the original diaphragm.
Exhibition Jr.'s are neat little reproducers that really dress up your Victor R.
They are like a petite version of an Exhibition reproducer. Probably a direct descendant of the "early" Gibson reproducers.

Cheers, Bob S.