Bill,
Your correct! Back in the day of tube type and hybrid TV sets, they were
shielded really good. The tuner and IF strip all had very good shielding, and
used a metal chassis. The cabinets then had aluminum foil glued all around the
insides, especially floor models. When they started to cheapen the cabinets
down in the early 80's, and go with strictly plastic console models, they
started skimping on the shielding to where now they hardly ever use it. About
the only thing with any shielding any more is the small combination tuner/if
section. There's no metal chassis anymore and everything is on a large PC
board. One of the best cures on new TV's and VCRs is to buy shielding foil and
liberally apply it yourself. Connect the shielding to the aquadag on the CRT
and down to the main ground on the chassis. Really, an extra ground should be
added to the line ground as where everything now is a hot chassis (no power
transformer) which makes it worse. Other equipment like computer, monit
ors, printers, etc needs this done also as you will hardly see any shielding
in any of them.
Best,
Will
*********** REPLY SEPARATOR ***********
On 10/14/05 at 12:24 PM Bill Fuqua wrote:
>Speaking of photos with the cover off. I have taken some photos
>like these before and I am amazed that up close that my digital camera
>still works. I expect that some don't work in intense RF fields. Also, one
>day while working on my 4-1000A amplifier I received a phone call. I was
>looking at the insides while it putting out a bit more than 2kW CW into a
>dummy load. It was not until after I finished the short call that I
>realized I was exposing the cordless phone to the strong RF field. I
>guess
>the reason it did not occur to me sooner was that the phone was working
>just fine.
> So, why is it that they can't make TV sets that will tolerate
>much weaker RF fields from our antennas half a block away? TV's have very
>little or no EMI shielding in them.
>
> Oh yes, about the photos, it looks like the glass envelope of
>tube on the left is scintillating due to electron bombardment. Nice red
>anodes as well.
>
>73
>Bill wa4lav
>
>
>
>At 10:33 AM 10/14/2005 -0500, Keith Dutson wrote:
>>What a neat set of pics! I love the look of plasma in the dark! Thanks
>for
>>sharing.
>>
>>73, Keith NM5G
>>
>>-----Original Message-----
>>From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
>>Behalf Of Jason Buchanan
>>Sent: Thursday, October 13, 2005 11:19 PM
>>To: amps@contesting.com
>>Subject: [Amps] Drake L4 with 3-400Z photos
>>
>>
>>All this talk about AC mains got me stirred up to take some nice photos of
>>Glow.
>>
>>I took the cover off my Drake L4 and took a few photos using a 60mm f/2.8D
>>micro Nikkor.
>>
>>http://n1su.us/tubes/3-400Z-bias.JPG
>>http://n1su.us/tubes/3-400Z-idle.jpg
>>http://n1su.us/tubes/3-400Z-pair.jpg
>>http://n1su.us/tubes/3-400Z-pair2.jpg
>>
>>
>>Enjoy.
>>
>>73 Jason N1SU
>>
>>_______________________________________________
>>Amps mailing list
>>Amps@contesting.com
>>http://lists.contesting.com/mailman/listinfo/amps
>>
>>_______________________________________________
>>Amps mailing list
>>Amps@contesting.com
>>http://lists.contesting.com/mailman/listinfo/amps
>
>_______________________________________________
>Amps mailing list
>Amps@contesting.com
>http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|
