QRZ! Ham Radio 4/QRZ Ham Radio Callsign Database - Volume 4.iso/digests/equip/940125.txt

Internet Message Format | 1994-11-14 | 21KB

Date: Tue, 26 Apr 94 04:30:19 PDT
From: Ham-Equip Mailing List and Newsgroup <[e-mail]>
Errors-To: [e-mail]
Reply-To: [e-mail]
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Subject: Ham-Equip Digest V94 #125
To: Ham-Equip


Ham-Equip Digest            Tue, 26 Apr 94       Volume 94 : Issue  125

Today's Topics:
              *** AM TRANSMITTER HELP/ADVICE ** (2 msgs)
          Blew up preamp in my RF Concepts RFC2-317 (again)
                      FT416 extended AM receive
                         Icom 736 Opinions???
                KENWOOD 850SAT - Experiences (2 msgs)
                        loop antenna (2 msgs)
              New Kenwood 144 MHz & 430 MHz FM/SSB Rigs
                     Radio Shack's New DSP Filter
                          Ramsey 20M SSB Rig
                         Steinbrecher Radios
                            Wide Band Ht?

Send Replies or notes for publication to: <[e-mail]>
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Problems you can't solve otherwise to [e-mail].

Archives of past issues of the Ham-Equip Digest are available
(by FTP only) from UCSD.Edu in directory "mailarchives/ham-equip".

We trust that readers are intelligent enough to realize that all text
herein consists of personal comments and does not represent the official
policies or positions of any party.  Your mileage may vary.  So there.
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Date: Sun, 24 Apr 94 19:48:01
From: ihnp4.ucsd.edu!agate!usenet.ins.cwru.edu!eff!news.duke.edu!concert!mms![e-mail]
Subject: *** AM TRANSMITTER HELP/ADVICE **
To: [e-mail]

Regarding screen vs. plate modulation, I seem to remember that it's rather
difficult to achieve 100% modulation via the screen modulation method, while
100% via plate modulation is a bit easier to achieve.  I also remember that
screen modulated transmitters ALWAYS sounded a bit thin in the audio when heard
on the air.

------------------------------

Date: Mon, 25 Apr 94 14:11:53 EDT
From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!news.intercon.com!news.pipeline.com!malgudi.oar.net!hypnos!voxbox![e-mail]
Subject: *** AM TRANSMITTER HELP/ADVICE **
To: [e-mail]

[e-mail] writes:

>
> Regarding screen vs. plate modulation, I seem to remember that it's rather
> difficult to achieve 100% modulation via the screen modulation method, while
> 100% via plate modulation is a bit easier to achieve.  I also remember that
> screen modulated transmitters ALWAYS sounded a bit thin in the audio when hea
> on the air.

Also, because complex waveforms such as the human voice are
often asymetrical it is important to observe the correct
"polarity" of the audio modulation transformer secondary.

Incidentally, 100% modulation is not only easier to achieve; it is
easy to OVER modulate. Boy, does that sound terrible!!


/----------------------------------------------------------------------\
| Jim Grubs, W8GRT            Voxbox Enterprises    Tel.: [phone] |
| [e-mail]   6817 Maplewood Ave.                      |
| Fido: 1:234/1.0             Sylvania, Ohio 43560                     |
\-+--------------------------------------------------------------------/

------------------------------

Date: Mon, 25 Apr 1994 20:48:46 GMT
From: amd!netcomsv!netcomsv!netcom.com![e-mail]
Subject: Blew up preamp in my RF Concepts RFC2-317 (again)
To: [e-mail]

In the 2M sprint last week, I toasted the preamp in my RFC 2-317 2M 170W
brick. Same modus operandi as last time - hit it with ~50W briefly due to
mis-adjusted transverter (normally 30W is max drive) and !poof!, no more
RX preamp. The Kantronics/RFC help-line is 100% busy, so can someone who's
familiar with the unit or killed one before tell me (1) which transistor(s)
should be replaced, and (2) any suggestion as to where I get them?
I'm not too worried about absolute top performance (as in realignment);
I just use the preamp to compensate for my brilliant engineering feat of
putting the tower 100' from the house (I do have power out at the base of
the tower where the brick is installed).
--->  Thanx for the advice!  73 Dave WB0GAZ [e-mail]  <---

------------------------------

Date: 25 Apr 94 10:59:57 CDT
From: ihnp4.ucsd.edu!dog.ee.lbl.gov!agate!msuinfo!uchinews!cdsmail!timbuk.cray.com!walter.cray.com!bexar.cray.com![e-mail]
Subject: FT416 extended AM receive
To: [e-mail]

In article <2pbf3s$[e-mail]>, [e-mail] wrote:

> I just bought a FT416 (_love_ it) and heard about a simple keyboard
> mod to enable extended receive that includes 119MHz+ AM.  The mod was
> to hold down the up/down arrows while turning the radio on.  No go.
> Anyone know anything about this?  Thanks in advance!
>
Way I understand it,  if a CPU reset is done by holding the MR and VFO
while turning it on, this will reset the frequencies to 144-148 (also lose
your memories).  Then, if you do the arrow keys/power-on,  you'll have the
extended RX from 130-174, and TX from 140-150.

Never verified this, as mine had these extended freqs out of the box.  If
you do hear about rx down to 119+AM, please share info!!!

- Tom Baltz
  [e-mail]

------------------------------

Date: 25 Apr 94 17:27:12 GMT
From: dog.ee.lbl.gov!newshub.nosc.mil!news![e-mail]
Subject: Icom 736 Opinions???
To: [e-mail]

I looked at an IC-736 at a dealer recently.
It does look like their 737, but I'm told some problems with the 737
were corrected in this rig.

I like the display, and controls better than some radios, but couldn't
buy this radio for my own use because it:
  * does not support external 12v power for portable/mobile operations.
  * has receiver gaps between some bands

I use a Kenwood TS-690 and Yeasu FT-650 now and like both of these
radios better than this one.

Roger Keating - KD6EFQ
[e-mail]

------------------------------

Date: Mon, 25 Apr 1994 14:30:20 GMT
From: ihnp4.ucsd.edu!sdd.hp.com!col.hp.com!fc.hp.com![e-mail]
Subject: KENWOOD 850SAT - Experiences
To: [e-mail]

: >I purchased a new one and kept it for a while and absolutely hated it.
: >The SSB is dirtier then anything else on the market (suprios emssions
: >only 28 to 32 db below fundamental, ack! cheezy).

: Tanvir's '850 had something wrong with it.  I have had one for over a
: year and love it.  I have gotten tons of unsolicited "outstanding audio"
: 73 es gl Bill,  W7LZP

If you check out the QST review of the 850 they also noted the xmiter
being a bit dirty on SSB at higher power levels. They weren't very
impressed with the design of the 12 volt final section. Who knows how
much you will actually notice this on the air.

73, Jay K0GU                 [e-mail]

------------------------------

Date: 25 Apr 94 10:11:59 -0600
From: ihnp4.ucsd.edu!usc!math.ohio-state.edu!darwin.sura.net!atlas.tntech.edu![e-mail]
Subject: KENWOOD 850SAT - Experiences
To: [e-mail]

In article <[e-mail]>, [e-mail] (Bill Turner) writes:
> In article <[e-mail]>,
>  <[e-mail]> wrote:
>>
>>
>>I purchased a new one and kept it for a while and absolutely hated it.
>>The SSB is dirtier then anything else on the market (suprios emssions
>>only 28 to 32 db below fundamental, ack! cheezy).  If you decide to
>>run it with an Amplifier, hope you have very co-operative neigbours.
>>The power supply I got made noise and I sent is back and they send me
>>a new one.  Still the same (seem like power supply have bug) after
>>changing it couple of times.
>>
>>
>>Tanvir
>>WN1P/3 (Living now in the state of PA).
>
>
> Tanvir's '850 had something wrong with it.  I have had one for over a
> year and love it.  I have gotten tons of unsolicited "outstanding audio"
> comments using a $19.95 Radio Shack mike, and have heard lots of 'em on
> the air with no evidence of splatter.  Well, ok, I just remembered I did
> have to homebrew a preamp for the mike - one op amp, no biggie - the
> mike amp is a tad short on gain unless you use the factory mikes.  The
> only complaint:  would like the noise blanker to be more effective.
> Part of the reason I bought it was that it has two (count 'em!)
> blankers, but my little Uniden 10 meter rig in the car has a far
> superior blanker.  A letter to the factory got the usual "gee, never
> heard that complaint before" answer.  Well, then they're not listenting
> because I have heard other hams on the air with the same complaint.  If
> that were fixed, it would be perfect....!
>
> Bill,  W7LZP
>
Well, glad someone posted this. I have had my 850S for about 2 years. I have a
Power supply built by a ham in North Tennessee. I think the 850 is one of the
best transceivers on the market. I operate a lot of CW and Pactor.. using FSK.
.the rig excells.. after reading the bad comments about SSB .. I got back on
the air with it on SSB. I consisitently get glowing audio reports. I spent some
time asking for detailed reports recently. Without exception they were all very
postive.

This caused me to ask what the story was with this guy's rig. The 850S is a
contest level rig. There are LOTS of bells and whistles.. that's the good
news.. the bad news is that if you don't set your controls correcty, your
audio will be terrible. There is a monitor feature that helps in this respect
and the versatility of the digital metering is very useful. .if the rig is
working correctly and you set it up .. it will work great.

Also have 2 friends that have the 450s and both love them. .we used the 450
during field day.. worked great.. think it is a BIG improvement over the 440
(our university club has the 440..never really impressed with it).

73

Jeff, AC4HF

------------------------------

Date: 25 Apr 94 10:04:18 -0600
From: ihnp4.ucsd.edu!usc!math.ohio-state.edu!darwin.sura.net!atlas.tntech.edu![e-mail]
Subject: loop antenna
To: [e-mail]

I am currently testing the MFJ Super Hi Q loop for an article I am working on.
I have been giving some good hard thought as to how to write this one up. I
honestly believe in the case of this antenna it isn't quite as simple as
comparing it to dipoles or beams. The loop, in my opinion, is a specialized
antenna. It is made for people who have limited space or want portability.

If you have the room for wires.. a variation of the G5RV (ZS6???) works
great.. with a simple tuner you can work 80-10 and will be pleased with the
results. It can be assemble VERY inexpensively, and works great for Field
Day and portable operation.

The loop DOES work. I have decided to really check it out by mostly operating
QRP with it. The loop works 10-30 meters. I have used it on 15,20,30 so far.
This has been due to the band conditions. I have worked both CW and SSB. I have
gotten excellent signal reports. The effectiveness of the loop as with all
antennas has to do with many variables.. what is near it, what type of ground
do you have in your area, is there water nearby, how high up is the antenna,
how high up is your QTH and what are the band conditions like.

I currently have 8 transceivers and 4 antennas hooked up for testing.. I can
easily switch between combinations for on the air comparissons. I think data
on the theoretical gain of an antenna is important.. but there are suffecient
variables involved to force you to look at how the antenna will perform for
you under your conditions. When I first put up my Gap Vertical I found that on
a given day my dipole would beat it out, another day the gap will outperform
the dipole. The band of operation, and the distance to the other station are
also important.

Getting back to the loop. I brought the loop along on a recent QRP expedition
we did. I hoisted it up about 30 feet into a tree and had it set up vertically.
Currently I have a short piece of PVC pipe and have the antenna set up
horizontally about 1 foot out of my tower up at about 22 feet. I have some
real good coax feeding it. I have had very good results with the antenna.

The tuner takes a little getting use to. Another aspect of this antenna is that
it is a hi Q antenna. There is definetly less noise on the antenna.. but if you
move a little bit on frequency.. you must retune the antenna. If you are going
to call CQ this isn't a problem, if you are going to tune around a lot, you
MUST take this into consideration. EX: you are on 14.255.. no one there.. you
get tired of calling CQ.. you tune to 14.265 and hear a station and want to
talk to him.. retune time. While on the same band this is done with a fine
tuning button.. and only takes a second or two.. but you will probably have to
move slightly off his frequency, hope it is clear and then retune.. and then
hope he is still there.

hope this helps

Jeff, AC4HF

------------------------------

Date: Mon, 25 Apr 94 14:18:59 EDT
From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!news.intercon.com!news.pipeline.com!malgudi.oar.net!hypnos!voxbox![e-mail]
Subject: loop antenna
To: [e-mail]

[e-mail] (I can't log out!) writes:

> tuning button.. and only takes a second or two.. but you will probably have t
> move slightly off his frequency, hope it is clear and then retune.. and then
> hope he is still there.

As always, a receiver noise bridge is the preferred way to tune.
Radiates NO signal.


/----------------------------------------------------------------------\
| Jim Grubs, W8GRT            Voxbox Enterprises    Tel.: [phone] |
| [e-mail]   6817 Maplewood Ave.                      |
| Fido: 1:234/1.0             Sylvania, Ohio 43560                     |
\-+--------------------------------------------------------------------/

------------------------------

Date: 25 Apr 1994 13:59:00 GMT
From: ihnp4.ucsd.edu!sdd.hp.com!hpscit.sc.hp.com!news.dtc.hp.com!col.hp.com![e-mail]
Subject: New Kenwood 144 MHz & 430 MHz FM/SSB Rigs
To: [e-mail]

A careful scan of the May QST reveals that some dealers are
advertising two new rigs from Kenwood.

    TM-255A   FM/SSB 2 Meter Transceiver  40W    $929.95  (AES Price)

    TM-455A   FM/SSB 70 CM Transceiver 35 W     $1079.95  (AES Price)

Both are relatively small, in a mobile radio format but I am not
sure of their exact size. AES has the TM-255A in stock, but not the
TM-455A (still waiting from Kenwood).

Editorial comment: Geez that seems like alota money for single band all mode.

Bob Witte / [e-mail]  / Hewlett Packard PMO / KB0CY  / [phone]

------------------------------

Date: Mon, 25 Apr 1994 16:56:38 GMT
From: ihnp4.ucsd.edu!swrinde!cs.utexas.edu!convex!news.duke.edu!eff!news.kei.com!world![e-mail]
Subject: Radio Shack's New DSP Filter
To: [e-mail]

In article <2p66mv$[e-mail]> [e-mail] writes:
>In <[e-mail]>, [e-mail] (Muenzler, Kevin) writes:
>..............
>>4.  The NOISE mode works quite well to remove the harshness from the
>>background noise on
>>    the lower bands (40 and down).  My receiver is pretty good at doing that
>>anyway so
>>    I was not really impressed with the noise filter.
>>
>..............
>
>Ar you sure that the noise filter works?  Perhaps a difference that
>you heard were from different bandwidths of NR and SSB modes.
>According to another ham, a discussion with RS DSP developers on
>Compuserve revealed that RS DSP has no NR function to keep the price
>down.  Then, descriptions of NR function would be just a misleading
>marketing.
>
>
>Ignacy Misztal              Ham radio: NO9E, SP8FWB
>E-mail: [e-mail]
>University Of Illinois      1207 W. Gregory Dr., Urbana, IL 61801, USA
>tel. [phone]         Fax: [phone]
>

There is a Noise Reduction setting on the front panel, but I have not
noticed any difference from the SSB setting. The SSB and CW modes work
well, and at 71 dollars ($79.99 less 10% for a preferred customer card)
I think the thing is very good.

It would be nice if it had a decent denoiser (the W9GR denoiser beats it
by quite a bit), but it does a very respectable job as an automatic
notch, and as a variable bandwidth filter on SSB and CW.


--
---------------------------------------------------------------
Daniel Senie                 Internet:     [e-mail]
Daniel Senie Consulting                    [e-mail]
508-779-0439                 Compuserve:   74176,1347

------------------------------

Date: Mon, 25 Apr 1994 17:37:39 GMT
From: amd!amdahl!netcomsv!netcom.com![e-mail]
Subject: Ramsey 20M SSB Rig
To: [e-mail]

In article <[e-mail]> [e-mail] writes:
>I just received a new catalog from Ramsey. The catalog is a bit slicker than
>their previous ones and it looks like they've expanded their line quite a bit.
>
>The most interesting item I saw was a new 20M SSB transceiver that comes either
>in kit form or assembled. Kit price was $350 if I remember correctly. Power
>ouput is 10W. It sounded knd of interesting. I wonder how it compares to the
>MFJ rig.


It's clear, and no secret, that a number of people have experienced and
reported serious problems with Ramsey products.

Given that, and given that this is a much more heavy investment than
the VHF and UHF rigs which are the subject of so much negative comment,
I'd sure wait for an impartial (read "QST") review to pass by before
sending in my deposit.

I'm sure Mr. Ramsey will disagree with my assessment of QST as impartial;
on the other hand, I haven't found either Wayne's World or CQ to really
cut to the chase when the product under review is made by an advertiser.

For its part, I sure hope QST doesn't wait around to review this critter!
It's apt to be both popular, and given past experience, can reasonably be
expected to provide a 'target rich environment.'

I sincerely hope that it's a wonderful, worth-while, high-quality product.
But clearly, some customer caution is the order of the day.

Naturally, one wonders whether producing 10 watts of SSB on 20 Meters is
*worth* an investment of $350 and the time required a-building, but that's
soley a personal decision.


Greg

------------------------------

Date: Mon, 25 Apr 1994 11:21:06 -0400
From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!math.ohio-state.edu!cis.ohio-state.edu!news.sei.cmu.edu!bb3.andrew.cmu.edu!andrew.cmu.edu![e-mail]
Subject: Steinbrecher Radios
To: [e-mail]

I just read an article in FORBES ASAP by George Gilder about Steinbrecher
radios.  In the article he claimed that Steinbrecher had invented a
broadband mixer that is almost completely free of spurious signals.  This
sounds almost too good to be true.  Is it?  If so, why is the technology
not in amateur radio equipment?

Thanks.

Keith Poole

------------------------------

Date: Sun, 24 Apr 94 09:39:00 -0600
From: ihnp4.ucsd.edu!usc!math.ohio-state.edu!news.acns.nwu.edu!news.eecs.nwu.edu!fidogate.nuars.nwu.edu!nwugate.fidonet.org!f747.n115.z1.fidonet.org![e-mail]
Subject: Wide Band Ht?
To: [e-mail]

On 21 Apr 94 03:01pm, [e-mail] wrote to All:

 J> Does any HT exist that can cover from 2meter to 173.MHz?
 J> How much does it cost
 J> and where can I find one?

"J":
The Bendix King LPH 5142 would meet your requirements, it is VERY wideband
(144-178) and has the added feature of being type-accepted for use outside
the ham bands, since that is it's primary sales area. You would give up some
functionality, the display reads only channel numbers, but if this were used
frequently by yourself, it shouldn't be a problem. Street price for a new
one is about 800 list, but if you check with a communications dealer, they
often have used ones with very little use, I got mine for 550 and it had
about 12 hours total time.

Check the yellow pages in your area for the Bendix/king dealer in your area,
most will deal slightly for cash. Accessories are available and battery life
is nothing short of phenomenal, the built in battery saver is very good at
extending the life of the battery.

If you buy one, try to get one with the display keyboard included. The
keyboardless ones have to be programmed by a computer cable, whereas the
keyboard models can be programmed via the keyboard if you know the right
tricks.

73 WL7BF

PAUL SPATZEK

... Benji! Don't run into the street! *#$@#? NO TERRIER
 * Evaluation copy of Silver Xpress. Day # 135
 * Silver Xpress V4.00

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End of Ham-Equip Digest V94 #125
******************************