[Amps] AL-1200 Tuning Capacitor Range

Alek Petkovic vk6apk at bigpond.com
Sat Oct 18 04:25:14 EDT 2014


G'day Kim.

Dunno if the AL-1200 is the same as the AL-1500 where the markings on 
the front panel indicate that the plate cap should be tuning at the spot 
you mentioned.

Yeah, I know. Different tube but knowing Ameritron, they probably have 
the same silk screening pattern for both amps.

With my AL-1500, its actually up a bit from that mark at the "17" position.

If your amp puts out the expected full grunt at that fully open 
position, then perhaps you shouldn't worry too much about it.

If not, then Dave's suggestion may be good advice.

73, Alek.
VK6APK

On 18/10/2014 1:05 PM, Dave Hachadorian wrote:
> Reduce the inductance.  This is usually most easily done by spreading 
> out the turns on the 21 MHz coil.
>
> Dave Hachadorian, K6LL
> Yuma, AZ
>
>
> -----Original Message----- From: Kim Elmore
> Sent: Friday, October 17, 2014 9:43 PM
> To: amps at contesting.com
> Subject: [Amps] AL-1200 Tuning Capacitor Range
>
> I have an AL-1200 that works very well using the 3CX1200A7 tube, but at
> the bottom end of 15 m the plate tune capacitor needs to be almost
> completely unmeshed for proper tuning. The load control is not near
> either extreme. I'm not completely convinced the PA is properly tuned; I
> figure this one has just a wee bit more stray capacitance. Would moving
> the 15 m tap one turn help this? If so, which way should I go: remove a
> turn or add a turn of inductance?
>
> Kim N5OP
>
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>

-- 
 From Sunny Binningup


---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com



More information about the Amps mailing list