I recently bought a remote band controller unit, the LTA RBC-1.
The unit works fine on all bands except 160 meters. On 160 meters,
the unit will sometimes start chattering like the relays are getting
very low cycle AC. This happens especially on TX on 160, but it
also happes just in RX on 160!
Note that these results occur with everything else stripped off --
i.e. rig is straight into a good dummy load, external ant relay box
completely disconnected.
In other words, the problem is definately between the IC-761 and the RBC-1.
I see no problems with the 2-foot cable connecting the 761 & the RBC-1
via 7-pin DIN. I suspect the RBC-1 is not getting quite the voltage it
expects to see on 160m, perhaps the voltage is right on the 'threshold'
between 160 & the next band. Perhaps engaging the TX varies that
volage ever so slightly that it 'oscillates' bewteen relays. I have
not yet gone in to look at the volatges from the 761 to the RBC-1.
I thought I would ask here and see if anyone else has used this unit,
and if there might be any suggestions. Again, the unit works FB on
all bands except 160. Any help greatly appreciated.
Thanks, Kirk WR3O WR3O@music-city.tdec.state.tn.us
>From n1jm@dreamscape.com (John Merrill) Fri Aug 9 19:27:29 1996
From: n1jm@dreamscape.com (John Merrill) (John Merrill)
Subject: OmniVI vs FT1000MP
Message-ID: <320B8311.59D@dreamscape.com>
Trying to decide on one or the other. Any words of wisdom out there?
John N1JM
>From tree@lady.axian.com (Larry Tyree) Fri Aug 9 19:59:23 1996
From: tree@lady.axian.com (Larry Tyree) (Larry Tyree)
Subject: Little projects
Message-ID: <199608091859.LAA11230@lady.axian.com>
Just a quick reminder about teh upcoming internet SprINT contest tomorrow.
If you missed the rules, let me know and I will send you a copy.
I like to use these contests as a warm up for the "big" sprint and as
a place to test new ideas in sprint type operating. This has led to
some little projects that I have finished with and want to share
with my contesting brothers.
PROJECT #1 - RX antenna input for the TS-850S
This is near the top of everyone's list when they are asked "What things
bug you about the TS-850S". I initially overcame this deficiency by
modifying my amplifier so I could connect a different receive antenna
to the TR relay. However, I wanted to change things so there wasn't as
much RF getting into the RX antenna due to close proximity to the
amplifier's output. This became a problem when using the same receive
antenna on a second radio (you know two radio operating was going to work
its way in here somehow).
Ville, OH2MM had provided me with instruction on how he modified his
TS-850S to have a separate RX input and this inspired me to try it.
Here are some simple steps to hopefully inspire others:
It took me an unrushed two hours to do all this.
1. Remove the top panel (you don't need to take off the bottom one.
2. Remove the plate which sits between the fan and the back of the
radio. This covers the output filter PC board.
3. Unsolder the connections to the SO-239 output connector.
4. Remove the three cables from the PC board next to the SO-239. This
includes two coax and one 3 conductor harness.
5. Remove the two screws holding in the PC board and remove it.
6. Locate the trace that goes from the relay's normally closed contact.
You can use an ohm-meter to find it - probe from the wire that went to the
SO-239. You will find a short trace on the back of the board which runs
to a chip capacitor. Cut this trace and solder some very small coax
to each side of the cut - connect ground to the nearby ground trace.
Make the cables about 4 inches long.
7. Remove the antenna tuner. There are 2 screws in the back and front (you
will need a magnetic screw-driver) and one on the side. You will need to
carefully unplug two wire harnesses and one coax connector.
8. Drill two holes for phono jacks on the back of the radio. Be careful
not to obstruct the screw hole for one of the screws in the back of the
antenna tuner. The best place is between the RF output connector and
the groundpost. Put them on top of each other and as close to the bump
on the back panel as possible. I used a vacuum cleaner while drilling to
make sure no metal chips went anywhere.
9. You will find a small hole under the SO-239 where you can feed
the two coaxs through. Solder them to the phono jacks and reassemble
everything. I put back to back diodes on the RX antennas input, but
you may not want to do this. A better thing would be to add a relay to
disconnect the RX antenna input when transmitting. I took care of
that in project #2.
10. Obviously, you will need a jumper cable to make your receiver
work again.
PROJECT #2 - The switch box:
Parts list - 4 position rotary switch
DPDT 12 VDC relay
1 K Ohm pot (optional)
12 phono jacks (or you can get by with 9)
mini box for above and knobs.
Clamp diode for relay coil if not included in relay
This box does two things: disconnects the receive antenna input when
transmitting and allows selection of the transmitting antenna or one
of three RX antennas when receiving. The pot can be used for RF
attenuation if your rig doesn't have one.
The relay gets controlled by the PTT output from your rig that normally
would go to your amplifier. Then one set of the contacts is used to
key your amplifier. Don't forget to put a diode across the coil of
your relay if there isn't one internally. Otherwise, you will have
undesired arcing across the contacts of the relay in your radio.
The other set of contacts disconnect the output of the rotary swtich
when transmitting. The rotary switch selects either the signal
coming from the transmitting antenna (from the TR relay in your rig)
or one of three receiving antennas. I use two phono jacks per RX
antenna so I can feed them to other boxes for other radios. I also
use two jacks for +12 volts so I can jumper power to another box.
You can build up one of these boxes in an hour or two. You can epoxy
the relay to the mini box.
If you want the pot there to act as an attenuator, I just hook it
up like you would a volume control: one end is ground, the other end
goes to the output of the rotary switch and the wiper goes to the
output. Use shielded cable as much as possible to avoid stray
pickup.
Have fun!!
Tree N6TR
tree@contesting.com
>From hwardsil@wolfenet.com (Ward Silver) Fri Aug 9 20:05:02 1996
From: hwardsil@wolfenet.com (Ward Silver) (Ward Silver)
Subject: RF exposure
Message-ID: <Pine.OSF.3.95.960809112909.21872D-100000@gonzo.wolfenet.com>
First, I think this discussion is VERY pertinent on the contest reflector
because we are the highest profile emitters in the hobby, save for some of
the EME boys. If there are regulations and legal issues raised as a
consequence, we will feel it first. We are "on the point" as Sarge always
used to say on "Combat"...and you know what always happened to the guy on
the point.
>From Dave LeDuc;
>
> So far in all of the comments that I have read no one seems to be concerned
> about any ill effects to themselves or their families that might occur as a
> result of exceeding the FCC RF guidelines. Could it be because no one
> believes that they are based on any scientific facts? Some people still
> believe that cigarette smoking is not harmful.
>
It is too easy for us to dismiss out-of-hand any suggestion that high RF
levels may be harmful. However, there is a paucity of data indicating
that exposure such as from ham installations can cause *any* measureable
effect. I don't sit in the beam of the antenna, I don't stick my hand
into VHF amplifiers, and I don't run smoke; these I know are not good.
Given that this hobby is filled with OF's that have been exposed for
upwards of half a century, casual exposure doesn't seem too harmful. I am
willing to listen to anyone that can show repeatable, measureable
effects...but I have seen NONE...yet.
If I thought for a minute that I was subjecting my family or neighbors to
anything that would cause health problems (other than the stress of RFI to
poorly-designed applicances), then I would be lowering my power output or
off the air immediately.
Reasonable safety precautions - yes. Regulations that will apply to
almost none of us, yet indicate to the lay public that we must be bad
because RF has been regulated - no.
> Is anyone familiar with the naval communications station that was
> once located in Cutler Maine? When I was a navy radioman back in the late
> 60's they transmitted using 1 megawatt power CW and RTTY, 24 hours a day. I
> understand that residents of the area were unable to use florescent light
> bulbs. It would seem to me that the residents may have been exposed to RF
> in excess of the current guidelines. I wonder if there has been any
> significant level of cancer or other diseases found in the area?
>
This is exactly my point about chronic vs. intermittent exposure.
Stations like the big point-to-point and ship-to-shore transmitters run
nearly continuously...this is chronic exposure. People that live under
power-lines or near unbalanced low-voltage/high-current feeders are
receiving chronic exposure. People that live near hams receive only
intermittent exposure with a fairly low duty-cycle.
I think we *do* need standards for chronic exposure. I think we *don't*
have *any* reason to regulate intermittent sources. I can't say that
there will never be any reason to regulate intermittent sources, but I
have seen nothing in any literature (I am not an expert, but very widely
read...) that would suggest such exposure has any measureable effect,
other than related to heating. Heating only occurs at very high exposure
levels and is a different phenomenon than what is being looked for as a
result of low-level exposure, namely metabolic and genetic-related
alterations to normal cellular processes.
To place this in perspective, if there is no provision for the regulation
of handheld 800MHz cellular phones, then the regulations are not
addressing the most meaningful issue extant in telecommunications safety.
73, Ward N0AX
>From gswanson@arrl.org (Swanson, Glenn, KB1GW) Fri Aug 9 21:07:00 1996
From: gswanson@arrl.org (Swanson, Glenn, KB1GW) (Swanson, Glenn, KB1GW)
Subject: HAARP
Message-ID: <m0uowx9-000f4fC@mgate.arrl.org>
Funny you should ask...
See September QST -- there's an article that tells you all about this
system.
"The High Frequency Active Auroral Research Program." Page 33-35.
73, Glenn, KB1GW
E-mail: kb1gw@arrl.org
-- ARRL HQ --
----------
>>By the way - during all of this, the Department of Defense is firing
>>up a multi- Gigawatt transmitter at the HAARP site at Gakona, Alaska.
>>For God sakes, if we're worried about 50 watts - what effect does
>>1,000,000,000.00 EIRP watts have? They are not worried about our
>>health! de KL7HF
>>
-------------------------------
>Is this the American version of the Russian Woodpecker? What will it do
>to CONTESTS?
>
>Zack W9SZ
>
>
>--
>
>
>From SANDELKW@usaanc.hou.xwh.bp.com (Sandel, Kyle W) Fri Aug 9 22:18:00 1996
From: SANDELKW@usaanc.hou.xwh.bp.com (Sandel, Kyle W) (Sandel, Kyle W)
Subject: No subject
Message-ID: <320BAB97@txpci6.hou.xwh.bp.com>
REVIEW
>From km9p@contesting.com (Bill Fisher KM9P) Fri Aug 9 20:31:05 1996
From: km9p@contesting.com (Bill Fisher KM9P) (Bill Fisher KM9P)
Subject: OmniVI vs FT1000MP
Message-ID: <Pine.BSD/.3.91.960809152914.27546A-100000@paris.akorn.net>
On Fri, 9 Aug 1996, John Merrill wrote:
> Trying to decide on one or the other. Any words of wisdom out there?
Yep. I've owned both. Buy the FT1000MP. The Omni-6 is a great radio
for chewing the rag on CW. I would still own one if that is all I did.
But as a contester, the radio falls short of my expectations. All of the
problems I encountered revolved around a buggy microprocessor.
73
Bill, KM9P
>From gswanson@arrl.org (Swanson, Glenn, KB1GW) Fri Aug 9 21:47:00 1996
From: gswanson@arrl.org (Swanson, Glenn, KB1GW) (Swanson, Glenn, KB1GW)
Subject: No subject
Message-ID: <m0uoxaE-000f4kC@mgate.arrl.org>
Funny you should ask...
See September QST -- there's an article that tells you all about this
system.
"The High Frequency Active Auroral Research Program." Page 33-35.
73, Glenn, KB1GW
E-mail: kb1gw@arrl.org
-- ARRL HQ --
----------
>>By the way - during all of this, the Department of Defense is firing
>>up a multi- Gigawatt transmitter at the HAARP site at Gakona, Alaska.
>>For God sakes, if we're worried about 50 watts - what effect does
>>1,000,000,000.00 EIRP watts have? They are not worried about our
>>health! de KL7HF
>>
-------------------------------
>Is this the American version of the Russian Woodpecker? What will it do
>to CONTESTS?
>
>Zack W9SZ
>
>From k6sti@n2.net (Brian Beezley) Fri Aug 9 20:52:18 1996
From: k6sti@n2.net (Brian Beezley) (Brian Beezley)
Subject: Free Near-Field Analysis Software
Message-ID: <199608091952.MAA11031@ravel.n2.net>
As a result of the recent FCC ruling that mandates RF-exposure limits for
amateur stations beginning January 1, 1997, I'm making available at no cost
a special version of AO Antenna Optimizer software that calculates electric
and magnetic near fields. NF.EXE requires a 386 or better, math
coprocessor, VGA, and DOS 3.0 or later.
You can download the 245K NF.ZIP file from ftp://n6nd.nosc.mil. You may
copy this free software for others as long as no charge is involved and the
software is used for amateur purposes only.
After you unzip the file, see READ.ME for more information. Please
carefully read the section on accuracy limitations of near-field modeling.
I hope this software helps hams evaluate their stations for compliance with
the new FCC rule. The software should be especially useful at high-power
contest, DX, and EME stations.
I'm providing this free software without support. The package includes
extensive documentation and 92 example antenna files. I hope you'll refrain
from calling, writing, or e-mailing questions about downloading or using the
software. Thanks!
Brian Beezley, K6STI
k6sti@n2.net
>From 71111.260@CompuServe.COM (Hans Brakob) Fri Aug 9 20:59:00 1996
From: 71111.260@CompuServe.COM (Hans Brakob) (Hans Brakob)
Subject: RF Exposure
Message-ID: <960809195859_71111.260_EHM78-1@CompuServe.COM>
Dave, K1EPJ asked:
>Is anyone familiar with the naval communications station that was
>once located in Cutler Maine? When I was a navy radioman back in the late
>60's they transmitted using 1 megawatt power CW and RTTY, 24 hours a day. I
>understand that residents of the area were unable to use florescent light
>bulbs. It would seem to me that the residents may have been exposed to RF
>in excess of the current guidelines.
Yes, I'm familiar with the station at Cutler and the sister-station at Jim
Creek, WA. Both would have been great 160M contest stations. The
antenna at Jim Creek was (is?) stretched between two mountains.
Interestingly, neither station would be subject to these guidelines since
their operation was below .3MHz!
73, de Hans, K0HB
Master Chief Radioman, USN(Ret)
>From gswanson@arrl.org (Swanson, Glenn, KB1GW) Fri Aug 9 22:26:00 1996
From: gswanson@arrl.org (Swanson, Glenn, KB1GW) (Swanson, Glenn, KB1GW)
Subject: HAARP
Message-ID: <m0uoyDF-000f5SC@mgate.arrl.org>
Funny you should ask...
See September QST -- there's an article that tells you all about this
system.
"The High Frequency Active Auroral Research Program." Page 33-35.
73, Glenn, KB1GW
E-mail: kb1gw@arrl.org
-- ARRL HQ --
----------
>>By the way - during all of this, the Department of Defense is firing
>>up a multi- Gigawatt transmitter at the HAARP site at Gakona, Alaska.
>>For God sakes, if we're worried about 50 watts - what effect does
>>1,000,000,000.00 EIRP watts have? They are not worried about our
>>health! de KL7HF
>>
-------------------------------
>Is this the American version of the Russian Woodpecker? What will it do
>to CONTESTS?
>
>Zack W9SZ
>
>From gswanson@arrl.org (Swanson, Glenn, KB1GW) Fri Aug 9 22:33:00 1996
From: gswanson@arrl.org (Swanson, Glenn, KB1GW) (Swanson, Glenn, KB1GW)
Subject: HAARP
Message-ID: <m0uoyI7-000f5SC@mgate.arrl.org>
Funny you should ask...
See September QST -- there's an article that tells you all about this
system.
"The High Frequency Active Auroral Research Program." Page 33-35.
73, Glenn, KB1GW
E-mail: kb1gw@arrl.org
-- ARRL HQ --
>From gswanson@arrl.org (Swanson, Glenn, KB1GW) Fri Aug 9 23:05:00 1996
From: gswanson@arrl.org (Swanson, Glenn, KB1GW) (Swanson, Glenn, KB1GW)
Subject: HAARP
Message-ID: <m0uoylG-000f89C@mgate.arrl.org>
Funny you should ask...
See September QST -- there's an article that tells you all about this
system.
"The High Frequency Active Auroral Research Program." Page 33-35.
73, Glenn, KB1GW
E-mail: kb1gw@arrl.org
-- ARRL HQ --
>From jholly@hposl62.cup.hp.com (Jim Hollenback) Fri Aug 9 19:13:36 1996
From: jholly@hposl62.cup.hp.com (Jim Hollenback) (Jim Hollenback)
Subject: RF exposure
References: <9608091236.AA05651@chip.agfa.com> <320BD436.2F12@alaska.net>
Message-ID: <9608091113.ZM6913@hpwsmjh1.cup.hp.com>
On Aug 9, 5:13pm, Jan & Del Seay wrote:
> Subject: Re: RF exposure
> Dave LeDuc wrote:
> >
> > So far in all of the comments that I have read no one seems to be concerned
> > about any ill effects to themselves or their families that might occur as a
> > result of exceeding the FCC RF guidelines. Could it be because no one
> > believes that they are based on any scientific facts? Some people still
> > believe that cigarette smoking is not harmful.
> >
> > Is anyone familiar with the naval communications station that was
> > once located in Cutler Maine? When I was a navy radioman back in the late
> > 60's they transmitted using 1 megawatt power CW and RTTY, 24 hours a day. I
> > understand that residents of the area were unable to use florescent light
> > bulbs. It would seem to me that the residents may have been exposed to RF
> > in excess of the current guidelines. I wonder if there has been any
> > significant level of cancer or other diseases found in the area?
>
> Exactly, Dave! Studies have not been run with any serious objective.
> And - the power level you're talking about would have very visable
> results.
> By the way - during all of this, the Department of Defense is firing
> up a multi- Gigawatt transmitter at the HAARP site at Gakona, Alaska.
> For God sakes, if we're worried about 50 watts - what effect does
> 1,000,000,000.00 EIRP watts have? They are not worried about our
> health! de KL7HF
>-- End of excerpt from Jan & Del Seay
But, this is the government doing it. And as we all know, the government
is not affected by its own rules. Look at all the superfund sites that
are occuring by the shutdown of military bases. For years they were doing
things that would have senior executives of private corporations in jail.
But this is interesting points, but really, what is the exporsure for
people living nearby? I know at the Davis transmitter site for San Francisco
com sta, people were miles away, except for the site personnel. Not
that I am defending the MPE rules, but the transmitter sites mentioned
might not be good cases to look at. A better thing to look at might
be VOA sites and commercial shortwave stations. Power levels in the
10-100k and probably people alot closer.
73, Jim, WA6SDM
jholly@cup.hp.com
>From slazar19@sgi.net (Spike Lazar) Fri Aug 9 23:20:53 1996
From: slazar19@sgi.net (Spike Lazar) (Spike Lazar)
Subject: RF exposure
Message-ID: <199608092220.SAA17269@orion.bv.sgi.net>
Hi All,
While injesting all opinions of this subject, I would like to see some
post from people who have not been exposed to this rf hazard. Who is
running this asylum anyways? Considering all the flatulence I have read,
(pro and con) we cannot put all the blame on 40 years of solder chewing.
Sincerely,
dr. Bafoofnik
p.s., All you newbies, please don't send me e-mail asking what solder is!
>From t.morrison@liant.com (Tom Morrison) Fri Aug 9 18:30:00 1996
From: t.morrison@liant.com (Tom Morrison) (Tom Morrison)
Subject: HAARP
Message-ID: <9608092229.AA10068@rmc.liant.com>
Zack W9SZ writes:
"Is this the American version of the Russian Woodpecker? What will it do
to CONTESTS?"
With some luck, create an F layer??
73, K5TM
Tom Morrison, T.Morrison@liant.com
Liant Software Corporation
512-719-7019 FAX:512-719-7070 WWW: http://www.liant.com/
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