[Elecraft] Incorrect Voltmeter Reading

Fri Mar 5 17:04:01 2004

I have a similar problem with my 4 band K1.  The K1 battery voltmeter reads
say 12.0 volts when the actual voltage is 12.3-12.35 volts.  I was thinking
my battery supply was about to give out when indeed it wasn't.  I have
since made a note on my "quick reference" guide I carry around with
the transceiver and mentally add 0.3 volt to the reading that appears
on the LCD panel.
Anbody else notice this with their K1?
73,
Sandy W5TVW
K1 #1178
----- Original Message ----- 
From: "Fred Bongard" <[email protected]>
To: <[email protected]>
Sent: Friday, March 05, 2004 9:01 AM
Subject: [Elecraft] Incorrect Voltmeter Reading

| While checking the power output of my K2, (3600's serial #), I noted 
| that the voltmeter reading is incorrect. I am using a 50 Amp (yes, 
| fifty Amp) Astron power supply with 4 ft of 16 ga wire going to the 
| radio. The Astron is set to provide 14.1 V. Using a DMM (and my trusty 
| Simpson 260) I read 14.0V at the power plug going into the K2 while in 
| receive. The Elecraft internal voltmeter reads 13.5 VDC. On transmit, I 
| get 13.9 volts at the plug and 13.1 volts on the Elecraft voltmeter.
| 
| It gets even more interesting. My antenna is a SteppIR vertical which 
| typically has a 1.4-1.7 VSWR on all bands (I still need to do a bit of 
| calibration to get it flatter). On those bands with the best match, I 
| get about 15W out of the K2 (no antenna tuner) and the Elecraft 
| Voltmeter reads 13.1 V while the DMM still reads 13.8-13.9VDC. On those 
| bands with a little higher VSWR, the output of the Elecraft drops to 
| 10-11 W and the voltmeter reads 12.8-12.9 VDC while the DMM still reads 
| 13.8-13.9VDC. I am measuring the power output with a Bird and a 100W 
| slug. In all cases I have the power set for max on the K2. When its 
| output (and voltage both drop) the K2's power meter also drops to about 
| 6-8 W (in which case the power output actually exceeds the power 
| "request" on the dial). When I operate into a dummy load, I get at 
| least 15W out on all bands, with the power meter reading about 15, but 
| the voltage display still drops to about 13.1 VDC (Current is about 2.5 
| A according to the K2). Receive appears to function normally.
| 
| I would appreciate any thoughts about 1) the apparently misreading K2 
| voltmeter and 2) the precipitous drop in power with a relatively small 
| SWR
| 
| Thanks
| 
| Fred Bongard
| WB6JLL
| 
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