[TenTec] Omni VII Current Draw

[Bob McGraw - K4TAX]

I recently received a recent e-mail pertaining to the current draw of the 
Omni VII.  Thought I'd share the exchange as others might have the same 
question.

<snip>
Hello Bob!
    Always enjoy the technical discussions on the various TenTec grouPS and 
am amazed at the patience and diplomacy you demonstrate during what 
otherwise could be difficult exchanges.
    I know we have discussed the OMNI VII current vs. power out on the 
various bands. I admit that I have lost those e-mail exchanges and wonder if 
you have a matrix of power / current drawn by band that you could send my 
way. I seem to have rather high current, with reasonable SWR and would like 
to run a similar matrix on my 07.
<snip>

My response and findings:

This morning I did a quick run through the bands and noted the amp meter on 
the power supply.

160M - 16.5A
80M  -  19.2A
60M  -  19.5A
40M  -  17.5A
30M  -  18.0A
20M  -  19.2A
17M  -  20.5A
15M  -  16.7A
12M  -  20.8A
10M  -  17.8A
 6M  -   19.8A

These measurements were made as my station is configured, thus the output of 
the Omni VII goes through a 2 position coax switch.  From there through the 
Centurion amp input.  From the output of the Centurion {The power meter is 
on the line between the Centurion amp and the tuner selector switch}  to 
another coax switch that selects one of 2 tuners.  One of the 4 outputs of 
the 238 tuner has an external 50 ohm load that was used for these 
measurements.  Hence, there are several switches, the path through the amp 
although it was off, various cables and such.  Noted that these do actually 
contribute to a bit of loss in power.  Power output on all bands was noted 
to be ~90 watts +/- 5 watts.  From this info I can see that the radio might 
draw some ~22 amps on some bands and load configuration.

As I recall, the last time I did a RF transmit power alignment on the bench 
the radio produced 100 to 105 watts on all bands. This was done with the 
Bird 43P and a 50 ohm load and only short coax jumpers to connect the 
required pieces of equipment.

Time for a commercial:   -  I have a Diawa CN-801 HP power meter that I have 
found compares very favorably with my Bird 43P and a known accurate slug. 
Actually I like the Diawa better than the Bird 43P for station use as the 
Diawa has peak hold and a couple of other nice features not found on the 
Bird meter.

Hope this helps.

73
Bob, K4TAX