Customizing; Installation - Ramsey Electronics PA1 Instruction Manual

CUSTOMIZING YOUR PA1 INSTALLATION:
Since it's up to you to supply the enclosure, connectors and any desired
operating conveniences, it's likely that each one of those thousands of PA1s in
use today has its own personality. For some good ideas, take a look at "Turn
Your HT into a 40W 2M Mobile Rig" by N8KDD in 73 Magazine, December
1989. The author's ideas are great, and we would only point out that his
mention of the PA1 assembly instructions pertain to the simple sheets supplied
prior to the publication of this manual. Also, we do find the relays supplied with
the RFS-1 kit to be quite suitable for the application.
The economy of the PA1, or even the factory-wired PA10, makes it possible for
you to set up permanent 40-watt rigs in various vehicles, at home, at the office,
all with their own permanent antennas, all of them ready to make your 2 Meter
HT or shirt-pocket wonder ever more versatile!
The hams at Ramsey Electronics thank you and hope you'll have as much fun
using your amplifier as you had building it!
INSTALLATION NOTES:
•
1. The best location for the relay is as close to the PA1 amplifier PC board
as possible with a short solid connection from the relay contact to
the amplifier input. If more than 1 inch, use coax.
•
2. All coax shields must be grounded with the shortest possible lead length
to your metal chassis ground point!
•
3. One short, solid ground path to power amp PC board (or metal chassis
or enclosure) is required.
•
4. Expect the relay to pull about 100 ma.
•
5. Miniature coax type RG-174 is ideal for all connections.
OPERATING NOTES:
1. If the relay chatters, it is a sign of high SWR, which you will wish to
resolve anyway by antenna system or amplifier output adjustments.
2. If the relay action is "sloppy", there may be insufficient RF to drive the
RFS-1 circuit. This can occur when using a "low power" HT setting
(È watt ) to conserve the HT battery, while still transmitting a good
5 watts from the PA1. The RFS-1 may be made more sensitive by
reducing the value of R2 to 1 or 2K ohms.
3. As designed, the RFS-1 will handle all input power levels safe for the
PA1 RF amplifier itself, up to 8 watts drive.
PA-1 • 13