[Boatanchors] Question: X-Rays from 3B28?

[George Babits]

I wouldn't loose any sleep over X-rays from the 3B28.  I've never heard of 
that before.  The X-Ray deal goes back to the old B&W TV rectifiers with 
their 1B3(?) or something like that.  I have heard of x-rays from the 866 
tubes.

My question is why would you waste a pair of 2500 volt rectifiers on a 450 
volt power supply.  The 5U4 or 5R4 would handle that with plenty of head 
room.

73,
George
W7HDL


----- Original Message ----- 
From: "William" <w_b_morton at hotmail.com>
To: "boatanchor" <boatanchors at puck.nether.net>
Sent: Friday, February 13, 2015 8:42 PM
Subject: [Boatanchors] Question: X-Rays from 3B28?


> Hello All,
>
> Been thinking of using a pair of 3B28 tubes to rectify an output voltage 
> to around 450VDC.  That value is above the critical anode voltage value of 
> 50V, so that should not be a problem.  Current is less than the 500mA max 
> listed in the table.  With the output voltage far lower than the ~1000V 
> values listed in the table, I think these things would not even break a 
> sweat.
>
> Two questions for the experts:
> 1.  Any issue seen operating arund 450VDC?
> 2.  The tubes have a sticker on the base with a warning regarding x-rays. 
> Why is there a warning on the tube base but nothing shown on the data 
> sheet?
>
> I had no idea these would present an x-ray risk based on what I saw (and 
> did not see) on the data sheet, so I picked up a pair.  Perhaps this my 
> learning experience for the week.
>
> Have a great weekend!
>
> Best Regards,
>
> William
>
> _______________________________________________
> Boatanchors mailing list
> Boatanchors at puck.nether.net
> https://puck.nether.net/mailman/listinfo/boatanchors