[Boatanchors] Plug in coils for Central Eletronics 10 B

[James M. Walker]

Congratulations,
and welcome to the Central Electronics users "club". First a few 
observations
You have the 10B, that's good, next if you "intend" to operate it as 
intended,
Ie; low power, get the RCA 6AG7 tube for the unit, then find, the changes
to the rig put out by CE, they will allow it to really sing well.

Find the VFO manual in some of the other manuals, 10A, 10B, 20A like
that. There are also mods to it. Some are OK, some I found were NOT
needed. My secret is the use of a spectrum analyzer and RF probes to
insure signal levels are correct, for injection and the like to each stage.

DON'T solid state the power supply, it won't get you much more than grief.
The 6AG7 only needs around 200 - 300 max plate volts. So make sure
you get at least that for the plates and that will be fine for the rest of 
the
circuitry that uses resistor networks to lower the values they need.

My VFO458 is per the manual, no extras, coil positioning per the manual
is OK and if you have an RF probe or analyzer you can determine if it is
working properly. Above all Don't Panic, if it seems to not be!

The plate coils can be fabricated from Air Dux or B&W coil stock, or
if you have a form you can do a handy coil once you settle on the bands you
want to operate. As for number of turns, check out any of the LP 
transmitters
and see what they used with the same caps as in the 10B, and trim to suit.

The coild forms are 5 pin for the plate of the 6AG7 and 6 pin for the input 
to
it.The manual in some cases calls for 2 watt resistors across the coils, I 
have
used 1 watt 5% and had no problems. If you are driving a "tube linear"
DON'T forget the swamping resistor at the 10B side. If solid state amplifier
turn the output down to the minimum needed to drive the rig and watch the
linearity of the "system".

Enjoy, the rig and VFO, I like mine!

Jim
WB2FCN
http://eshop1.chem.buffalo.edu

----- Original Message ----- 
From: "John King" <k5pgw at yahoo.com>
To: <boatanchors at mailman.qth.net>
Sent: Tuesday, February 06, 2007 12:27 PM
Subject: [Boatanchors] Plug in coils for Central Eletronics 10 B


> Hello folks!!! I have Central Electronics 10 B serial
> number 625 and a BC-458 VFO in what appears to be nice
> shape. That seems to be a real low serial number.
>
> I need the mixer plate coils and final amplifier tank
> coils. If I cannot get the coils, I need the six pin
> plug in coil forms to make my own. I have the 75 meter
> coils but I need a 40 meter plate tank coil and the
> higher band coils eventhough I understand the BC 458
> moves a lot on higher bands and operation up there is
> not desirable.
>
> I still want the coils and/or coil forms. Thanks for
> reading, looking and responding. 73, John, K5PGW
>
>
>
>
>
> ____________________________________________________________________________________
> Need Mail bonding?
> Go to the Yahoo! Mail Q&A for great tips from Yahoo! Answers users.
> http://answers.yahoo.com/dir/?link=list&sid=396546091
> _______________________________________________
> Boatanchors mailing list
> Boatanchors at mailman.qth.net
> http://mailman.qth.net/mailman/listinfo/boatanchors
> ** List Administrator - Duane Fischer, W8DBF/W9WZE **
> ** For Assistance: dfischer at usol.com **
> $$ For vintage radio info, see the HCI web site $$
> http://www.w9wze.org
>
>
>