To follow up, now that the amp is cabled.
As I suspected. I've never had a problem driving my amp to the legal limit
on AM (arguably 375W carrier with about 1500W peak out). I now effectively
have a 250W+ AM transmitter. With no modulation the thing puts out around
200W carrier. Output peaks run about 1200W, so there's obviously some
positive carrier shift going on. That's on 40M. On 20M, the most I can get
out of the radio with no modulation drives the AL-1200 to a measly 130W
resting carrier and a maximum of 1000W on peaks.
One could argue that the dB's are a nit, but this wasn't really a positive
change. The early v1 AM transmit DSP code was very very good.
BAD Andy!
Max Orion II output power seems ok, but now I can barely make 1500W on any
band. Used to do it with PWR set to around 90, now even at 100 I'm lucky to
see 1300 watts out of an AL-1200.
Grant/NQ5T
-----Original Message-----
From: Grant Youngman [mailto:nq5t@comcast.net]
Sent: Tuesday, September 12, 2006 9:13 PM
To: 'Discussion of Ten-Tec Equipment'
Subject: AM Output Level 2.037j
Has anyone figured out what's going on with AM transmit with the new
release?
I get a resting power out level in the 10+ watt range, with upward carrier
shift with modulation (erratic with around 25% peak positive shift on a
Belar mod monitor). The peak output with 100% modulation is running 70+
watts, or there 'bouts, which on average might imply the carrier is moving
up to something shy of 20 watts under modulation, give or take the side of a
barn.
This isn't all that terrific, if it's working the way it appears to be --
behavior more like a controlled-carrier modulation scheme (albeit with a
relatively slow time constant). And given the output levels, it's
questionable whether this new version is going to fully drive my AL-1200.
Haven't put it on the air yet on AM, so don't know if it's going to play at
the other end like a loud DX-40 or what :-)
I almost think a bit of downward modulation might be a better answer rather
than the way it was 'fixed" in the new release.
Then again, maybe I'm just missing something ...
Grant/NQ5T
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|