SWR meter instructions wanted

D

Des Bromilow

Guest
i,

I have an old SWR meter for 27MHz CB radios.
It's been several years (10) since I used it last and I've forgotten how to
drive it.
I recall something about having the switch in the "fwd" setting, pressing
transmit (keying the mic) then adjusting the needle for some setting, then
switching to "revse" and reading something, or something along those lines.

Help?

Also.. is there any issues with firing up some 27MHz AM/SSB rigs which are
approx 15yo? I know CB is fading in popularity, but I am curious of it's due
to regulations, or other influences (internet etc)

Des
 
Des Bromilow wrote:

i,

I have an old SWR meter for 27MHz CB radios.
It's been several years (10) since I used it last and I've forgotten how to
drive it.
I recall something about having the switch in the "fwd" setting, pressing
transmit (keying the mic) then adjusting the needle for some setting, then
switching to "revse" and reading something, or something along those lines.

Help?
Click to expand...
Your meter is probably able to measure either the standing wave ratio
(SWR) for an antenna, or else forward and reflected power separately
(which is another way of determining the same thing).

To measure SWR direct it should have a calibration setting and
adjusting knob which allows you to set the meter to the cal point on
the SWR scale while the transmitter is keyed. Once you've done that
switch to SWR and key again to read SWR ..... Or you can measure
forward and reflected power (on the appropriate switch settings and
scale) without calibrating.

Also.. is there any issues with firing up some 27MHz AM/SSB rigs which are
approx 15yo? I know CB is fading in popularity, but I am curious of it's due
to regulations, or other influences (internet etc)
Click to expand...
Probably no more so than any other piece of 15yo electronic equipment.
Power it up and if it works you're laughing... if it doesn't you've
got a repair job on your hands. No doubt a set that age would also
benefit from a complete alignment job -- if you've got the rest of the
necessary gear.

The reason for their fall from favour is that UHF CB is so much better
for short range communication (30km or so). They have a consistent
and reliable range at any hour of the day -- without the sky wave
effects.

--
John H

Hotmail is a spam trap, wbuauneirl@ovtcbaq.pbz will reach me if you apply ROT13.
 
"John_H" <john4271@hotmail.com> wrote in message
news:2ojq30pmbp4mbij4ga76l2r35n9fdt7vhb@4ax.com...
Des Bromilow wrote:

i,

I have an old SWR meter for 27MHz CB radios.
It's been several years (10) since I used it last and I've forgotten how
to
drive it.
I recall something about having the switch in the "fwd" setting, pressing
transmit (keying the mic) then adjusting the needle for some setting,
then
switching to "revse" and reading something, or something along those
lines.

Help?

Your meter is probably able to measure either the standing wave ratio
(SWR) for an antenna, or else forward and reflected power separately
(which is another way of determining the same thing).

To measure SWR direct it should have a calibration setting and
adjusting knob which allows you to set the meter to the cal point on
the SWR scale while the transmitter is keyed. Once you've done that
switch to SWR and key again to read SWR ..... Or you can measure
forward and reflected power (on the appropriate switch settings and
scale) without calibrating.
Click to expand...
Some older SWR meters just had the FWD and REF settings - use the FWD to set
the calibration, that is set to fwd, push PTT and adjust control so the
needle sits on the CAL mark on the meter, which is normally over near the
full scale deflection point.

Then select REF and push PTT to read the reflected power or SWR. Anything
below about 2:1 is acceptable although you may like to try and get as low as
possible.

If the SWR meter does have a PWR/SWR setting on the switch, then what John
said would apply, but if it's an el-cheapo oldie it may only have FWD/REF
settings....

Cheers

Martin, VK2UMJ


Also.. is there any issues with firing up some 27MHz AM/SSB rigs which
are
approx 15yo? I know CB is fading in popularity, but I am curious of it's
due
to regulations, or other influences (internet etc)

Probably no more so than any other piece of 15yo electronic equipment.
Power it up and if it works you're laughing... if it doesn't you've
got a repair job on your hands. No doubt a set that age would also
benefit from a complete alignment job -- if you've got the rest of the
necessary gear.

The reason for their fall from favour is that UHF CB is so much better
for short range communication (30km or so). They have a consistent
and reliable range at any hour of the day -- without the sky wave
effects.

--
John H

Hotmail is a spam trap, wbuauneirl@ovtcbaq.pbz will reach me if you apply
ROT13.
Click to expand...


---
Outgoing mail has been checked
Checked by AVG anti-virus system (http://www.grisoft.com).
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Thanks,

these instruction match what I have.

thanks,
Des
"Martin, VK2UMJ" <vk2umj@REMOVEyahoo.com.au> wrote in message
news:c1mope$oak$1@austar-news.austar.net.au...
"John_H" <john4271@hotmail.com> wrote in message
news:2ojq30pmbp4mbij4ga76l2r35n9fdt7vhb@4ax.com...
Des Bromilow wrote:

i,

I have an old SWR meter for 27MHz CB radios.
It's been several years (10) since I used it last and I've forgotten
how
to
drive it.
I recall something about having the switch in the "fwd" setting,
pressing
transmit (keying the mic) then adjusting the needle for some setting,
then
switching to "revse" and reading something, or something along those
lines.

Help?

Your meter is probably able to measure either the standing wave ratio
(SWR) for an antenna, or else forward and reflected power separately
(which is another way of determining the same thing).

To measure SWR direct it should have a calibration setting and
adjusting knob which allows you to set the meter to the cal point on
the SWR scale while the transmitter is keyed. Once you've done that
switch to SWR and key again to read SWR ..... Or you can measure
forward and reflected power (on the appropriate switch settings and
scale) without calibrating.

Some older SWR meters just had the FWD and REF settings - use the FWD to
set
the calibration, that is set to fwd, push PTT and adjust control so the
needle sits on the CAL mark on the meter, which is normally over near the
full scale deflection point.

Then select REF and push PTT to read the reflected power or SWR. Anything
below about 2:1 is acceptable although you may like to try and get as low
as
possible.

If the SWR meter does have a PWR/SWR setting on the switch, then what John
said would apply, but if it's an el-cheapo oldie it may only have FWD/REF
settings....

Cheers

Martin, VK2UMJ




Also.. is there any issues with firing up some 27MHz AM/SSB rigs which
are
approx 15yo? I know CB is fading in popularity, but I am curious of
it's
due
to regulations, or other influences (internet etc)

Probably no more so than any other piece of 15yo electronic equipment.
Power it up and if it works you're laughing... if it doesn't you've
got a repair job on your hands. No doubt a set that age would also
benefit from a complete alignment job -- if you've got the rest of the
necessary gear.

The reason for their fall from favour is that UHF CB is so much better
for short range communication (30km or so). They have a consistent
and reliable range at any hour of the day -- without the sky wave
effects.

--
John H

Hotmail is a spam trap, wbuauneirl@ovtcbaq.pbz will reach me if you
apply
ROT13.


---
Outgoing mail has been checked
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.595 / Virus Database: 378 - Release Date: 25/02/2004
Click to expand...
 
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