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 Intermediate Frequency for an Essanay Bantum
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 Return to top of page · Post #: 1 · Written at 10:24:19 PM on 8 January 2018.
Samt's Gravatar
 Location: Hobart, TAS
 Member since 6 May 2013
 Member #: 1337
 Postcount: 72

I have an Essanay Bantum that needs an alignment. Would anyone know the intermediate frequency for this receiver? It is a 1937 model with the following valve lineup:
AF3
AK2
EBL1
80 rectifier.
Kind Regards, Sam

Essanay Bantam
Essanay Bantam
Essanay Bantam


 
 Return to top of page · Post #: 2 · Written at 10:56:08 PM on 8 January 2018.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5340

Are you sure that's the correct line-up?

The only 1937 Bantam that I can find is the model 80 with EZ2, EK2, EBF1, EL3N (IF = 455KHz)


 
 Return to top of page · Post #: 3 · Written at 11:37:02 PM on 8 January 2018.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3856

I have issues with that as well.

EBL1 would be a duo diode power output pentode with a top cap EL3N has no top cap: NOT pin interchangeable with EL3N.

AF3 is likely the IF Its a Pentode (remote cut off) Not withstanding that it just might be reflexed? & used to drive the OP Valve

AK2 Is an Octode so that will be the mixer oscillator,

#80 is correct as a full wave rectifier.

It is possible that it is 455Khz The unlikely alternative, only if it is actually earlier than 1937 is likely 175KHz

Is there a circuit? & what has been done to it? Nothing will not be a desirable answer, but there is good reason for asking.

Marc


 
 Return to top of page · Post #: 4 · Written at 4:11:58 PM on 9 January 2018.
Samt's Gravatar
 Location: Hobart, TAS
 Member since 6 May 2013
 Member #: 1337
 Postcount: 72

The radio is a bit of a mystery. It is dated at 1937 by the letter D on the licence transfer on the back. The radio is in a Bakelite cabinet with Essanay on the dial below a symbol of a Lyre. I assumed it was a bantam as that was the only model listed on Radio Museum that was produced in 1937 before Essanay ceased production, however it does not match the circuit for the Bantam. The radio appears to be factory wired for an EBL1 as the op valve as the grid is wired to the cap. The AF3 and AK2 were installed in the radio when I found it, however there is the possibility that they are the incorrect valve. I will study the wiring against the valve data. The rectifier valve is an 80 with a UX base instead of the EZ2 on the circuit diagram for the bantam which has the phillips side contact base.
I am guessing that Essanay either made two versions of the Bantum or this radio was built using a dial left over after Essanay ceased production.


 
 Return to top of page · Post #: 5 · Written at 8:03:39 PM on 9 January 2018.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5340

It may help in identification to send Brad some good clear photos.


 
 Return to top of page · Post #: 6 · Written at 9:06:14 PM on 9 January 2018.
BringBackTheValve's Gravatar
 Location: Linton, VIC
 Member since 30 December 2016
 Member #: 2028
 Postcount: 228

While on the subject, almost every picture I have sent has been slightly blurred.

My early shots were from my ipod, then I tried a cheap HD camera, which was no better.

Brad has been pretty tolerant so far, but I want to lift my game.

Is it me, my cheap crappy cameras, or both?

Here is my latest mess----standby for pictures.

Essanay Bantam
Essanay Bantam
Essanay Bantam
Essanay Bantam


 
 Return to top of page · Post #: 7 · Written at 9:06:37 PM on 9 January 2018.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1345

You can understand that if the business was in trouble they may have thrown together some radios using what parts they had. I have a built-during-the-war-years STC like that. The model stenciled on the chassis bears no relation to the actual circuit of the radio.

NOTE that the AK2 and AF3 have 4 volt heaters.


 
 Return to top of page · Post #: 8 · Written at 9:59:09 PM on 9 January 2018.
BringBackTheValve's Gravatar
 Location: Linton, VIC
 Member since 30 December 2016
 Member #: 2028
 Postcount: 228

Yikes! Sorry everyone.

I have crashed into a thread unintentionally. Got carried away by the blurry pictures comment.

I will continue on a more appropriate thread very soon.

Most regretful.


 
 Return to top of page · Post #: 9 · Written at 10:01:57 PM on 9 January 2018.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3856

It may have been a victim of the war as well as parts became short. I do get the occasional set where strange mods have been inflicted.

EZ2 is similar electrically to 6X5 and is listed as a heater rectifier. http://frank.yueksel.org/sheets/005/e/EZ2.pdf Its a "P" base, 6X5, Octal & #80 UX-4.

Now, how is it wired? EZ2 is 6.3V and #80 is a 5V filament valve. The filament cannot be grounded as its B+. How many volts (AC) are across the #80 big pins (filament)? 1561 is not out of the equation it is 4V filament and was "P"base, European 4pin & UX4..

The closer you get to an object, with a hand held camera, the faster (including flash) the shutter speed needs to be: You move, chassis does not. Tripod mounted camera always wins. Auto focus is not your friend & be prepared to step back to get enough "depth in field" & then crop. The higher the "f" stop number the greater is the depth in field.


 
 Return to top of page · Post #: 10 · Written at 10:12:51 PM on 9 January 2018.
BringBackTheValve's Gravatar
 Location: Linton, VIC
 Member since 30 December 2016
 Member #: 2028
 Postcount: 228

Maarc,

Thanks!

I did not think about a tripod.

It makes sense, because where the "shoot' buttons are mounted on both cameras forces the camera sideways while taking a shot.


 
 Return to top of page · Post #: 11 · Written at 10:16:36 PM on 9 January 2018.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5340

.BringBackTheValve: most modern digital cameras, including those in mobile phones, employ anti-shake technology. I have seen many otherwise in-focus photos ruined by camera shake, so factor that feature into your next camera purchase.


 
 Return to top of page · Post #: 12 · Written at 10:26:37 PM on 9 January 2018.
BringBackTheValve's Gravatar
 Location: Linton, VIC
 Member since 30 December 2016
 Member #: 2028
 Postcount: 228

Shall do G.


 
 Return to top of page · Post #: 13 · Written at 10:50:35 PM on 9 January 2018.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5340

 
 Return to top of page · Post #: 14 · Written at 5:28:49 PM on 10 January 2018.
Samt's Gravatar
 Location: Hobart, TAS
 Member since 6 May 2013
 Member #: 1337
 Postcount: 72

Hi Mark,

I measured the filament voltages and they are as follows:
EBL1 6v
AK2 4v
AF3 4v
80 rectifier 4v

I have emailed photos to Brad. This was my first attempt at radio repair as a teenager after this radio was given to me. The chassis was very rusty so I removed the rust and re painted the chassis by hand with a matching metal paint. I re capped the radio but was never able to get it working properly. It has been in storage for a while but I decided to attempt another repair now I have more experience with repairing valve equipment. I am about to replace the power cord with a new three cord cable.


 
 Return to top of page · Post #: 15 · Written at 9:29:29 PM on 10 January 2018.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1111

I wonder if the rectifier was originally a 4 volt type, something like AZ1 with the 4-pin base? I don't have my valve book with me at present so cannot suggest the correct type, but I'm sure Marcc will know.


 
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