Re: {Collins} Repainting tube shields



I have an S3 line and KWM2.  This is the first “S line” radio (although I read Blocksome’s article about how this radio really would have been next generation A line) that I have seen with shields on ALL of the tubes and only one is a true IERC (on the PTO tube).  This radio has about the best audio that I have heard.  I run the unbalanced output through a separate preamp and tube amp that I also use for my R390/20V2 AM station.  All tube sockets are designed for shields, but also shield that pretty hollow state warm “glow”.  I wonder which shields that it would be safe to leave off and which really are critical for shielding?  I’ll also “CC” the reflector and get a consensus.  Thanks for the advice, Jim!
73
Ty

Sent from my iPhone

> On Nov 4, 2017, at 15:42, Jim Haynes via Collins <collins@xxxxxxxxxxxxx> wrote:
> 
> My understanding is that only the IERC shields are good for helping cool
> the tubes below what they would run unshielded.  Now in some cases shields
> are needed for RF reasons, and in other cases they are used just to hold
> the tubes in their sockets when the equipment is shipped or subject to
> vibration.  So that it's better to take the shields off and save them until the equipment is to be shipped.
> 
> There are also the tube hold-downs which are like shields with big windows
> cut in them to allow air to circulate more freely.
> 
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