Hi Gary you will just get more volts out of it at higher curent......if that
drives the meter off-scale reduce the number of secondary turns, or use a
potential divider to reduce the voltage.
RF Thermo ammeters can be shunted, but my experiments so far suggest that
the scale does not quite "scale"...even taking care to use a "four terminal"
connection to avoid contact resistances......I'm still working on that one.
I dont think it was you testng this afternoon unless you now have a 1000ft
tower and 10kW :-))
Cheers de Alan G3NYK
[email protected]
----- Original Message -----
From: "G4WGT - Gary" <[email protected]>
To: "Rsgb_Lf_Group" <[email protected]>
Sent: 18 February 2004 20:01
Subject: LF: RF Current meter
Hi all at LF,
I have been conducting tests with QRS & DFCW now that I have completed the
DDS VFO & the antenna is back up after storm damage & everything seems to
be
ok.
The main reason for this e-mail is to ask this question,
"When I have looked at designs in amateur radio magazines or internet for
a
clip on RF Ammeter the designs seem to be limited to 2 ranges (100mA & 1A
FSD), is there a limit to the range of this type RF Ammeter or can the
ranges be extented to say 5 Amps maybe? is there a calculation to extend
the
range ?"
My LF antenna seems to be showing in excess of one Amp so I need an RF
Ammeter with a greater range than 1A.
73
Gary - G4WGT
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