adding a magic eye tube to an amplifier?

[ALBATROS1234]

I bought a Webster Chicago 81-1 wire recorder. It's been gutted to convert to a guitar amp. I cannot find a schematic online for this model 81-1. Tube compliment is 6SJ7, 6SN7,6V6 and 6X5 with a 6E5 eye tube. the leads are all cut. I want to built it into a single ended guitar amp and the eye to work as a level display and open and close as I play.Kinda how it operates when used as a recording level indicator. If someone has a schematic for this model or knows how to wire a magic eye to do what I want I would appreciate it. I just don't know even where to insert it or how. I imagine hooking it up in parallel with a preamp stage would be in the right direction but really don't know where to begin.TY

[kagliostro]

Look to the Selmer Zodiac Twin 30

https://el34world.com/Forum/index.php?action=dlattach;topic=14337.0;attach=31718


EDIT:

Other option, use one of this

https://www.ebay.com/itm/6E2-Magic-Eye-Tube-Audio-Level-Indicator-Music-Spectrum-Fluorescence-Display-/312674369874




Franco

[sluckey]

A few years back TubeGeek did some interesting magic eye projects. Search this forum. Hopefully the attachments haven't been purged.

[ALBATROS1234]

Thanks guys, Oh and happy 2020, although so far it looks like 2021 could be worse. Cheers

[shooter]

so far it looks like 2021 could be worse

depends on which side the curtain you're looking at 

[Sonny ReVerb]

I put an eye tube in one of my amps. The amp is an Epiphone/Gibson and Selmer hybrid with a Selmer style eye tube that oscillates with the trem speed and depth. Haven't tried one as a level meter, but it shouldn't be hard to adapt the Selmer circuit.

http://www.vintagehofner.co.uk/selmer/schematic/wire.html

[ALBATROS1234]

thank you sir. I just got this wire recorder cheap and although gutted it has the heart of a 5C1 champ with a 6SN7 added stage and a magic eye that I would like to do something its on the face of the thing and I think would look great if it responded to signal level or something besides sitting there. I wish it wasn't gutted. on the antique radio forum half the guys are like I don't get why you would want to do this.I am thinking....Its there.... the tube glows bright in my tester....magic eye tubes are cool as shit.... it would look great on this art deco looking unit openining and closing in response to my signal. this is out of my realm and I hoped someone here could be like oh yeah put is as a blah blah parallel to blah blah gain stage . I will eventually figure it out, just wish I had a schematic for this unit but the only one I can find has a 6J5 instead of a 6SN7 and no eye tube.

[PRR]

The schematic for the eye tube is on the eye tube datasheet.

Run a wire from the eye grid through a 470k resistor to a wire with a clip. Try that at various LOW-voltage points in the amp. Grid of the output stage is a good bet.

[munkeyboy]

Great thread,  I have a couple of these magic eyes I've been wanting to do something with.

Also, I have a revere T700d reel-to-reel that doesn't use magic eye, but two neon bulbs.   one for clean indicator, one for distortion.   As of yet, the clean indicator isn't working last i tested, but the distortion one is surprisingly accurate.  Once the breakup happens, the it lights up with the distortion. 

[trobbins]

Note that the eye target current could vary by a mA or more, which may require some attention as to the particular B+ connected to, especially if it is a preamp level B+ with lots of upstream dropper resistance.