Some picture about
Chinese GU-81M:
China made many GU-81Ms in end of 1950s to 1970s.It was called
FU-81 .
Here are some pictures:
New socket:
http://www.zmdz.com/bbs/incomefiles/20123/19535994724.JPG
and http://www.zmdz.com/bbs/incomefiles/20123/19551084489.JPG
I purchase this socket in our local FU-81 manufacturer
New old in stock. $35 ,foundry aluminium and ceramic,very rugged.
Old socket:
http://www.zmdz.com/bbs/incomefiles/20123/19552498497.JPG
http://www.zmdz.com/bbs/incomefiles/20123/19553966001.JPG
This socket pick up in our local flea market , just only $5!
tube:
http://www.zmdz.com/bbs/incomefiles/20123/19555110514.JPG
http://www.zmdz.com/bbs/incomefiles/20123/1956470990.JPG
This tube made by our lacal tube manufacurer in 1978.
you can see the different base ( ceramic), Russian is glass.
Chinese GU-81M still in high price level in China , quote $100 orso,
but few people want them.
But Chinese GU-80 is very inexpensive, This tube can replace GU-81 direct?
As far as I know, GU-80/80 have very good IMD performance but low output in
higher
band and difficult to match
, even can not work in 21MHz or higher.But I have no experience.
73!Hsu
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|