Tubes Asylum

Paging Jim McShane

108.200.223.64

Freo-1

Jim (and other Citation II boffins):

Was wondering what would be involved to configure a Citation II from ultra linear to pentode? I had read somewhere that Stu Hegman wanted to make the Citation II all pentode, but was overridden.

Personally, never been a fan of ultra linear. Would rather have a pentode with regulated screens.

What do you think?
" Don't look back. Something may be gaining on you"

Satchel Paige

Follow Ups:

RE: Paging Jim McShane - Steve O 15:03:44 11/04/23 (1)
If you haven't seen it already, check out recent AK thread where dcgilliespie converts a heath W5 from UL to pure pentode. Although the W5 is definitely not a Citation 2, basic conversion philosophies and considerations are discussed in typical dgc detail and should have application to a cit 2.
- Convert W5 to pentode (Open in New Window)
- RE: Paging Jim McShane - Freo-1 15:59:54 11/04/23 (0)
  Thanks to Jim and Steve for your feedback.
  " Don't look back. Something may be gaining on you"
  
  Satchel Paige
RE: Paging Jim McShane - Jim McShane 14:22:31 11/04/23 (3)
To do it right it would indeed require a high quality screen supply in addition to the Deuce's existing power supplies. Finding physical space for a new regulated screen supply could be a problem - it's crowded in the chassis already.

And it would require rewiring the octal sockets for the new output stage configuration along with disconnecting the UL tap connections from the OPTs.

It's really not that difficult if you can find the space in the chassis.
- Screens - Triode_Kingdom 21:39:19 11/04/23 (2)
  I think this is a terrible idea considering the market value of an unmolested Citation II. That aside, why would the screens need to be regulated? Wouldn't a LC network from B+ be sufficient? That's how they're handled in the "McShaned" Cit V. These doubler supplies are pretty stiff, and minimizing the DCR between that and the screens seems to do the trick.
  - I'm sure you are right - Freo-1 08:06:37 11/05/23 (0)
    The LC network from B+ would be sufficient. I just like overkill, but the chassis is already tight.
    
    I just think as good as the Citation II sounds, it would be good to hear what Stu Hegman (allegedly) had in mind to hear it in all pentode mode.
    " Don't look back. Something may be gaining on you"
    
    Satchel Paige
  - While a purist may cringe at modding a Cit 2 - Steve O 02:53:31 11/05/23 (0)
    The mods can be performed so that they're reversible. Consider too that "value" considerations may involve factors other than simple resale.

Post a Followup:

FAQ

Post a Message!

Forgot Password?

Moniker (Username):
Password (Optional):
	Remember my Moniker & Password (What's this?) Eat Me
E-Mail (Optional):
Subject:

Message:	(Posts are subject to Content Rules)

Optional Link URL:
Optional Link Title:
Optional Image URL:
Upload Image:
E-mail Replies:	Automagically notify you when someone responds.

To view your new posting or follow-up, click on the RELOAD or REFRESH button on your browser.

This post is made possible by the generous support of people like you and our sponsors:

Signature Sound

[ Signature Sound Lounge ]