Input vs. Output

[Floyd Sense]

The ratio of input power (plate volts * plate current) to output power is 
the efficiency of the output stage.  Efficiency is usually expressed as a 
percentage and the 60% or so that you're seeing is typical for that type of 
rig.  Transmitters for CW only ran the amplifier in class C, which was more 
efficient than the classes typically used for SSB, where minimizing 
distortion is more important than efficiency.  Check an ARRL Handbook for 
info on typical efficiency %s for the various classes of operation.

73, Floyd - K8AC

----- Original Message ----- 
From: "Tom Buchanan" <tlbuch at SCRTC.COM>
To: <HEATH at LISTSERV.TEMPE.GOV>
Sent: Saturday, December 10, 2005 1:01 AM
Subject: Input vs. Output


I just got my first tube type rig (Heathkit HW-16) on the air and have been 
enjoying making some contacts with it.  I notice the older rigs refer to RF 
power input and modern rigs RF power is output.  Is there a calculation to 
figure equivalency for input watts to output watts?

For example, the HW-16 manual specifies 50 to 90 watts input and on the 
antenna tuner/wattmeter it shows 30 to 60 watts output on 40m.

73,

Tom
KG4KGY

-----------------------------------------------------------
Products bought, sold or traded here is the responsibility of the
parties involved.  This list and the City of Tempe are not responsible
for losses or misrepresentations of any kind.  Buyer beware!

-----------------------------------------------------------
This list is a public service of the City of Tempe, Arizona
-----------------------------------------------------------

Subscription control - http://www.tempe.gov/lists/control.asp?list=HEATH
To post - HEATH at LISTSERV.TEMPE.GOV
Archives - http://listserv.tempe.gov/archives/HEATH.html

-----------------------------------------------------------
Products bought, sold or traded here is the responsibility of the
parties involved.  This list and the City of Tempe are not responsible
for losses or misrepresentations of any kind.  Buyer beware!

-----------------------------------------------------------
This list is a public service of the City of Tempe, Arizona
-----------------------------------------------------------

Subscription control - http://www.tempe.gov/lists/control.asp?list=HEATH
To post - HEATH at LISTSERV.TEMPE.GOV
Archives - http://listserv.tempe.gov/archives/HEATH.html