The PLL exciter is why you're having such good success running a 4-cavity
duplexer. If you had a PM exciter, chances are you'd be experiencing
desense. The PLL exciter produces about 22 dB less noise at 600 kHz offset,
reducing the noise supression requirement of the duplexer by a like amount.
Hmmm... I didn't realize the DVP has a wider IF. I gather DVP
requires up to 6 Khz of audio. So now I'm thinking that this
receiver is not suitable for my busy hill (Santiago Peak).
What do you think?
--
Tim
:wq
On Sep 6, 2010, at 8:17 PM, Jeff DePolo wrote:
The SP docs show
Not all voltmeters behave the same with complex AC waveforms (such as
noise). Some of my Flukes are inaccurate at higher AC frequencies (like
above a few hundred Hz) - and they're spec'ed that way. What kind of meter
are you using, and where are you measuring (speaker terminals is where you
Or speed up the CWID one or two WPM, or change to a slightly higher tone
frequency. Top 40 stations sometimes still do this trick (pitching up their
CD players or automation system playback speed maybe 1%) - some PD's are
convinced that it improves ratings for one reason or another...
I have tried with 3 volt meters and 2 SINAD meters: a Fluke
77, a Sinadder 3 (SINAD AC voltmeter) and a HP8924c.
Pretty much same results with all. That is 20 db quieting
around 0.7 uV, SINAD around 0.35. So what's the recommended
meter? Should I trust the SINAD reading and chock the
It looks like the FCC rules give you extra power when opting for dual
polarization.
No, they don't give you extra power. For commercial stations, horizontal
polarization is the standard. You can supplement it with vertical, either
as cross-polarized linear, or as elliptial/circular, but that
I'm doing this from memory - I have the docs at home and can verify later.
The DB lowband dipoles are 50 ohm feed Z due to the close spacing to the
tower leg.
1 dipole - fed directly with 50 ohm coax (VB-8)
2 dipoles - fed with equal legs of 50 ohm coax (VB-8) to a tee, match 25
ohms from tee
I don't know the current frequency, but suspect it's in the
460/465 MHz range. Will it move down into the 440s without a
lot of grief?
Yes.
Also, I don't need anywhere near 100 watts, and need to avoid
abusing the good nature and power bill of my landlord. (Also
hope to have battery
I'm assuming this is a CW beacon?
I would think that whether rockbound or synthesized, you'd probably be best
off having the oscillator running all the time and keying RF at a gain or
multiplier stage. You might have to do some keying waveform shaping to
avoid keyclicks. I'd take a real close
The deviation is 15 kHz, or you're seeing 15 kHz of bandwidth on the
spectrum analyzer? The latter would be normal, the former wouldn't be.
-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Tim Sawyer
Sent: Saturday,
Before we get into the math, an important question that needs to be answered
is whether or not this mix occurs when your repeater transmitter is unkeyed.
--- Jeff WN3A
-Original Message-
From: Repeater-Builder@yahoogroups.com
The simplified instructions for tuning an isolator are:
1. Tune input (tx port) for maximum return loss with antenna port
terminated in 50 ohms and reject load connected to reject port
2. Tune output (antenna port) for minimum insertion loss, sweeping from tx
port to antenna port, again with
But why? If all of the power (or, let's hope, at least
99.99% of it)
is
on-channel, *should* a properly-designed and properly-functioning
transmitter misbehave due to the poor match a duplexer presents at
frequencies far removed from the channel center?
Well yes, properly
Actually I think that even though Service Monitors have
finally become *relatively* commonplace in the Ham Shack, the
VNA is not something most hams have seen or know how to use.
For $100, Rick's (Amtronix) return loss bridge is a must-have for anyone
that has a SM with a SA/TG. With it,
Jeff, out of all the PAs you've seen out there, both commonly
used and not-so-common... which ones (in your opinion) are
properly designed (when working right)?
I think a lot of them, generally speaking, are properly designed. That's
not to say that some of them don't have some downsides or
I know I'm going to regret stepping into this one, but since when has that
stopped me before...
Thanks, Gary, for admitting the 43 doesn't measure power
directly.
What do you mean by measure power directly? If you're talking about
comparing a thruline measurement against
Because the impedance is not matched between the transmitter
and duplexer, the 'apparent' loss of the duplexer is greater
than the manufacturers stated loss of the duplexer. Changing
the cable length is not changing the loss of the duplexer,
it's changing the power that is accepted at
Jeff, you aren't stepping on my toes at all. Glad to see your
comments.
OK, good. Since you've never met me, I can assure you, you definately DO
NOT want me stepping on your toes, it would be painful.
I do have to agree with Kevin that most duplexer
manufacturers recommend different cable
So will someone post a simple rule of thumb. If you have the
option of optimizing cable length from PA to first cavity, IE
you haven't made them yet what's the best simple rule of
thumb to follow to build them to avoid reactance. 1/2wl if
allowed minus coupling loop depth? Or is that past
OK, I think, for the most part, we're on the same page. I'm cuttin' and
trimmin' a lot here...
And this is where I believe the duplexer manufacturers are
covering their butt. They don't want the problem with
complex reactance presented by the duplexer to be their
problem. Not that I
I'm going to take a stab at this, at the risk of possibly stepping on Gary's
toes.
1. RF amplifiers in general (not only solid state) don't *have* a 50 ohm
source impedance, they're (nominally) designed to work *into* a 50 ohm load.
The difference is subtle, but significant. Transmitters aren't
The amp does fine without the duplexer inline. Full power and
it follows the Mirage chart. But I had a thought (that's
SCARY) I pulled out my seldom used MFJ 259 and dialed in my
output. I plugged it into the duplexer TX side and noted that
it reads 39 ohms. I disconnected the remaining
I must have missed some posts - my inbox ran out of space (I'm on the road
and not checking email as often as I usually do), so my apologies if I'm
asking questions that have already been answered...
Allan Crites and I are currently in discussion which will
be used as the basis of a RB web
The grungy audio isn't related to the amp.
Yes, I know, you said that. My question was whether the grunge was there
whether or not the repeater transmitter was keyed.
The TKR may be turned down to 20-30 watts and not trip the
amp.
By not trip, do you mean not key or not cause the amp to
Before adding a Mirage 320 our TKR 750 was putting out 50
watts into a 6 cavity Wacom WP-642 at the cost of 2-3dB loss
on TX (as the spec sheet said.) The cans are tuned right on
the money and the Hustler G5-144 fed with LMR-400 is 1.1:1.
I'm guessing that's a G6...?
This has worked for
The cable length issue is a brother to if you don't like
your VSWR, change the point along the transmission line where
you're measuring it.
I don't know what that's supposed to mean. The VSWR on the line is the same
no matter where along the line you measure it. If you're using a meter
Can somebody please explain how the insertion loss of a duplexer is
properly measured using a HP 8920A (with specan).
1. Connect duplexer Tx port to duplex port on 8920.
2. Connect antenna port on duplexer to antenna port on 8920.
3. Go to spectrum analyzer screen.
4. Set center
...@yahoogroups.com] On Behalf Of Jeff DePolo
Sent: Friday, August 06, 2010 4:21 PM
To: Repeater-Builder@yahoogroups.com
Subject: RE: [Repeater-Builder] Measuring duplexer insertion loss
Can somebody please explain how the insertion loss of a duplexer is
properly measured using a HP 8920A
Florida Repeater Coordinator proposes narrowbanding:
http://www.florida-repeaters.org/FRC%202meter%20narrowband%20p
olicy%20released%207-18-10.pdf
Apparently Carson's Rule works different in Florida than it does everywhere
else.
--- Jeff WN3A
With 250mW (+24dBm) into the transmit port... antenna port is
a quality 50 ohm load, I see -72dBM at the receiver port. (pretty
much what I expect.. 1.8dB loss through the xmit side, 100dB
notch through the RX side.
Those numbers are fine.
With it all hooked up receiving an input signal
You did an excellent job of explaining the complex
interrelationships among
2m repeaters. However, not all 6m repeaters have a 1 MHz split; my 6m
repeater on Tranquillon Peak follows the California band plan
and has a 500
kHz split. The duplexer has four cans about 12 in diameter
and
At this point, I'm leaning towards the bad mojo/karma phase
of the moon!
Let's start out with the basics:
1. How much desense do you have?
2. How are you injecting the Rx signal, and what are you using for the
signal source?
3. What are you using for a dummy load when doing the desense
I wonder how many of the -53 naysayers have or have used a Cushman
CE-3? LOL! The folks that have looked at the output of one of
these on
a spectrum analyzer will get it.
K
Where I come from, we call that a comb generator, not a signal generator...
Ya gotta know the limitations of your
I think you (Skipp) may be confusing 130C with one of the other 3M products.
130C is the self-vulcanizing (self-amalgamating?) tape. It has no adhesive;
it's not sticky or gooey; itt doesn't leave any residue. In fact, it
doesn't even leave a black stain on connectors like regular vinyl
Kevin, I'm sorry to have to tell you this but I think your
calculator batteries need to be changed.
0 dBM = 0.2236 volts in a 50 Ohm circuit.
+20 dBM is indeed 100 mW and P=EI and inserting 100 mW into
the Eq. for Volts in a 50 Ohm system, E= the sq. rt. of the
quantity (.100 x 50) =
What is a good radio for building a one way 420 link? The
link will be for a remote receiver and will not need to be
duplex... RX at the voter and TX at the remote receiver. The
link RX has to live on a noisy hill. Thanks for your advice.
My preferences, in no particular order, would be
...
--- Jeff WN3A
--- In Repeater-Builder@yahoogroups.com
mailto:Repeater-Builder%40yahoogroups.com , Jeff DePolo
j...@... wrote:
What is a good radio for building a one way 420 link? The
link will be for a remote receiver and will not need to be
duplex... RX
Good thoughts Milt, and I'll add a few
While not an easy thing to find I would suggest that you most likely
need some sort of a bandpass cavity on the receiver to protect from
the noise that gets past the heliax notches.
Remember that a notch duplexer only removes the notched
portion
The holy grail for FM performance testing, which includes adjacent channel
rejection measurements, is EIA/TIA-603. I believe revision C is the latest.
Unfortunately, you'll have to pay to get a copy of that document unless you
can scrounge one up.
To summarize how the test is done (and I'm
Hi
you beat me to it, I would suggest a duplexer problem as -55dB
isn't a lot you should have ideally better than 80dB. It also could be
the fact that you are running too much tx pwr, have you tried dropping
it down.
73
Steve, M1SWB(UK)
He said he measured the Tx carrier at the Rx
Hi Jeff
yes I know -55db is I think around 399 microvolts
No, you're still missing it. He said -55 dBm (m = milliwatts), not -55 dB.
which will flatten any receiver
-55 dBm at 1 MHz offset isn't going to bother any half-decent receiver. A
decent receiver would have 100 dB of
Ok, now I hook the spectrum analyzer up to the receiver port,
and I see
about -55dBm. 50 watts = +47dBm, minus the 100dB notch =
-53dBm that is pretty close to what I'm seeing at the rx antenna port.
Question is: Should this good enough for a low band micor receiver?
Thanks,
Tim
Continuing to consolidate three warehouse/storage locations and getting rid
of some excess in the process. I posted some of these on another list but
still have a lot left, posting them here with ham discounts.
Qty 60+ RFS/Cablewave 738801 1/2 N female, NOS, military packaging (fits
Andrew
They're great radios. I'd strongly recommend a Delta-S (narrowband front
end) over a wideband SX or Rangr due to the front end being much tighter. I
have many UHF Delta-S's (probably about 60 or 70) on the air, mostly for aux
links, and have set up VHF and UHF Deltas as repeater radios, packet
Vector Electronics (Google vectorbord and circbord, not typos), GC
Electronics, and Radio Shack (if you can find a store still stocking them).
--- Jeff WN3A
-Original Message-
From: Repeater-Builder@yahoogroups.com
I took a quick look at them, and what stands out like a sore thumb is 1.6 db
insertion loss with a 150 watt power rating. That means they'll be
dissipating close to 50 watts in such a small package. Doesn't give me a
warm and fuzzy feeling...
--- Jeff WN3A
mountain tops with ice
and salt water sprays. They are expensive.
Fred W5VAY
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Jeff DePolo
Sent: Thursday, July 01, 2010 11:29 PM
To: Repeater-Builder
I'll echo most of Dave's comments, and add a few...
The MYA's tend to have finicky tuning, and I've never seen one sweep
correctly out of the box. Close enough probably, but not optimized
either. The BMOY's are broad band, with one model covering 406-440
MHz and another from 440-480 MHz.
To get the RF phase accuracy you're implying that is required would mean
that everything in the RF path would have to guarantee that phase
relationship. That means the same length RF interconnect cables inside the
cabinet, same RF feedline length (or full-wavelength multiples thereof),
same
Anyone have, or know of, a surplus of 1/2 line? I've been scouring the
surplus places, eBay, etc., but haven't found any decent deals. I can use
pieces or reels anywhere from a few hundred to a few thousand feet. RFS,
Andrew, et. al., anything but Commscope. Thanks in advance.
Yes, but you'll probably find them most often in Micor PURC (paging)
stations. Components of interest include the high-stability and
ultra-high-stability oscillators, simulcast control card, audio delay unit
(usually made by Allen Avionics), etc. By no means a state-of-the-art
system, but they
My Tessco account rep emailed me that they're running a promotion this week
- free shipping. So if you're thinking about buying a big repeater antenna
or a reel of Heliax, save big money on truck freight if you order this week.
--- Jeff WN3A
Are the cables coming from the GPS reference are the same
length at both sites?
Maybe I'm missing something here, but how the heck would the length of the
cable from the reference oscillator to the transmitter/exciter matter? It's
just the frequency reference (10 MHz or whatever) for the
Propagation delay in the coax.
Propagation delay doesn't affect anything on the reference output side of
the GPSDO. The phase of the reference oscillator can vary -- the
synthesizer doesn't care about the phase of the reference oscillator, only
the frequency. Likewise, the VCO output isn't
Everyone is entitled to make an ass out of himself now and then, but you're
abusing the privilege...
-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of kevin valentino
Sent: Sunday, June 20, 2010 9:21 PM
To:
Also our above mentioned power supply which operates our 2
Meter and 440 Repeaters and a low power link started humming
yesterday. A trip to the tower showed that the two large
wires coming from the Pass Transistors to the post on top of
the regulator board and into the 1000 Uf
I always use an NPN transistor (2N4401 or whatever floats your boat) as an
inverter on the Micor COR, with a voltage divider on the base. Micor COR
to base through 10K, 4.7K from base to emitter, ground emitter, collector
becomes active-high COR. Pull up collector with 12V through 1K (or
Here's how we've designed our controllers' COR, CTCSS, and
logic inputs for many years: Feed the COR signal to the top
of a voltage divider. The upper resistor is 10K and the lower
is 4.7K. Feed the junction of the divider to the base of an
NPN such as a 2N3904, 2N, etc. You'll
Have a 110 watt Mastr II station on 33 MHz that would be a nice 10 repeater
(or remote base for that matter), with power supply and cabinet, $200, pick
up only (Philly).
--- Jeff WN3A
-Original Message-
From: Repeater-Builder@yahoogroups.com
OK, you're looking for something in the middle then.
For parallel protectors, LEA CFS or SP series, or Transtector Apex II, may
be more in the price range you're looking for (under $1000). Since I don't
use protectors of that kind regularly, I don't have any other
recommendations other than to
that may have only a couple thousand dollars worth of
equipment inside?
Chuck
WB2EDV
- Original Message -
From: Jeff DePolo j...@broadsci.com mailto:jd0%40broadsci.com
To: Repeater-Builder@yahoogroups.com
mailto:Repeater-Builder%40yahoogroups.com
Sent: Tuesday, June 08, 2010 4:22
Probably the ones I've had the most luck with are the Islatrol series from
Control Concepts. I think they have been bought out by Emerson or Liebert
or one of the other companies that have power divisions. Anyway, they call
these active tracking filters. They not only are TVSS's but also
If I want the caps changed, is there anyone in particular at
Crescend I
need to talk to? I wasn't aware that they would support the
Milcom line.
No, just fill out the RMA form from their web site. You might want to ask
for an estimate or quote before you send the unit in, but they'll want
I have a friend running a 75W Micor UHF repeater and he needs
to operate it for a single user who uses regular PL tone. My
friend has a PL module installed on the Tone Squelch board in
I presume you mean audio-squelch board.
Does he need a single PL tone encoder card for the card cage?
Hello to group,
Is putting a MOV from hot to ground, neutral to ground, on
the primary of the transformer of the power supply a good idea..
I have a ICE surge suppressor on in front as well but thought
I would put more inside the supply for back up.
I'm not that big of a fan of MOV's, but
28-29 amps is on the high side. Are you using the amp at more than maybe 5
MHz or so from the original frequency? Some of the Milcom/Crescend amps are
tunable, but many used fixed-value metal-clad mica capacitors in the base
and collector matching. The values of the caps and/or their placement
Start with the basics:
1. Clean all of the contact pins and female contacts with a good contact
cleaner like Deox-It. When re-installing each of the boards/cards, check
check to make sure that all of the male pins are straight and that none of
the female contacts have spread - tighten up by
@yahoogroups.com
mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of Jeff DePolo
Sent: Sunday, May 30, 2010 8:39 AM
To: Repeater-Builder@yahoogroups.com
mailto:Repeater-Builder%40yahoogroups.com
Subject: RE: [Repeater-Builder] Re: Help Needed (Guidance and
advice) tuning
a DB Products
] On Behalf Of Jeff DePolo
Sent: Monday, May 31, 2010 6:09 AM
To: Repeater-Builder@yahoogroups.com
mailto:Repeater-Builder%40yahoogroups.com
Subject: RE: [Repeater-Builder] Re: Help Needed (Guidance and
advice) tuning
a DB Products Duplexer
Mine don't have labels on them. Usually they were
--- In Repeater-Builder@yahoogroups.com
mailto:Repeater-Builder%40yahoogroups.com , Jeff DePolo
j...@... wrote:
Ok so here's what I've got (I think)
http://www.n2ckh.com/FORSALE/REPEATERS/DUPLEXERS/DB4076/DSC02678.JPG
Hamvention special, 4 cavities, appears to be a DB Products
4076
Ok so here's what I've got (I think)
http://www.n2ckh.com/FORSALE/REPEATERS/DUPLEXERS/DB4076/DSC02678.JPG
Hamvention special, 4 cavities, appears to be a DB Products
4076 family unit. My bench tools: HP 8924c w/ Spec Analyzer
and Tracking Generator.
There was a guy at the Hamvention
I would look for a shorted tantalum capacitor hanging
somewhere on the
10V rail.
I agree.
If you hook 10V from an outside source to the 10V
buss, you'll
probably find it's drawing all kinds of current. The 10V regulator
circuit will go into fold back before burning up. This is by
Leaving for Dayton tomorrow morning (weather forecast has improved a bit,
looks like both Saturday and Sunday will be decent). After Dayton I'm
headed to Evansville, IN. Any repeater-builders out there with machines
between Dayton and Evansville (via Cincinnati and Louisville - I-75, I-71,
Our usual clan which includes a number of repeater-builder denizens will be
in 2370 et al, at the end of a row. Come by for free 807's and bring lots
of money to buy stuff, nothing I bring to sell is coming back home with me
this year...
Long-range forecast for Dayton doesn't look all that
Building a PL decoder out of NE567's is old-school, and I've never seen a
design that didn't have drift problems.
The MX-COM (now CML Micro) tone chips were a better way to go, but many have
been discontinued. If you can find them on the surplus market, that would
be the easiest way to go. The
Hi Skip,
What Booth are you going to be in at Dayton?,Will you be going?
Wesley AB8KD
P.S. I want to see how Ugly you are
There are plenty of people at Dayton much more ugly than Skipp - anyone who
has attended Dayton before knows what I mean :-)
When he's not mowing down pedestrians
Depending on the PL-259 in question (i.e. who manufacturered it), sometimes
you can get them onto FSJ2 without any problem, other times you need to take
a bit off the threads to get it to thread onto the shield.
But to complicate matters, some PL-259's are manufacturered such that the ID
in the
I'm guessing I am not the first to want to do this...
I want to use a UHF Micor for a link. I want to be able to stop the
PL encode immediately when a user unkeys, but I want the controller
to be able to hold the transmitter up (without PL tone) for
sending IDs.
There appears to be
@yahoogroups.com
Subject: Re: [Repeater-Builder] Micor PL encoder modification
(TLN5731A)
Jeff DePolo wrote:
Pin 701 on the board (base of Q704) is PL Inhibit - pull to
ground to kill
the encoder.
Thanks Jeff,
I did notice P701 on the schematic. Any experience on whether
Hi,
I have read that one can put plain low cost PL259 connectors
on FSJ1-50A Andrew 1/4 inch suplerflex using a UG-176 reducer.
Yep.
Can the same be done with the Andrew LDF1-50 1/4 hardline?
Nope. The OD of the shield is too big to fit into a UG-176 reducer. FSJ1
is exactly a
Trylon, through Tessco, Hutton, et al.
--- Jeff WN3A
-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Gran Clark
Sent: Monday, May 03, 2010 2:56 PM
To:
I don't have a schematic in front of me, but if your plan is to key voltage
to the board on/off, this won't work ideally because the vibrasender reed
takes a little time to come up to speed.
Since the repeater transmitter is still keyed long after a user unkeys, just
muting the encoder seems
UG-176 ?
Try the reducer meant for RG-8X.
On Mon, May 3, 2010 at 11:21 AM, Jeff DePolo
j...@broadsci.com mailto:jd0%40broadsci.com wrote:
Hi,
I have read that one can put plain low cost PL259 connectors
on FSJ1-50A Andrew 1/4 inch suplerflex using a UG-176 reducer.
Yep
How about doing it without a reducer at all then?
According to this the dielectric size of RG-8 is 0.285
and LDF-1 is 0.29
Cant find the dimensions of the shield of RG-8 but it brings the size
of LDF-1 to 0.30 which should fit nicely inside a PL-259.
Just calipered (is that a word?) a
Because of the internal desense issue, I'd build them the same, but operate
the two radios separately. That is, use one as a transmitter and the other
as the receiver by default. No duplex mods required. If the Tx dies on
one, swap the system cables around to make the formerly-transmitter
I appreciate the thoughts. Anytime I've looked at a scheme
which allows simply swapping the TX and RX to get back on the
air, I arrive at the same conclusions...
(1) If I took a lightning hit at the site, I'd want my spares
to have been stored somewhere else.
(2) Once I swap the TX and
Message -
From: Jeff DePolo mailto:j...@broadsci.com
To: Repeater-Builder@yahoogroups.com
mailto:Repeater-Builder@yahoogroups.com
Sent: Tuesday, April 20, 2010 5:46 PM
Subject: RE: [Repeater-Builder] Sinclair C-Series cable lengths
I
I have 2 C-Series bandpass cavities, with individual I.L. set
at 1.0 db each. When I couple them together and measure, I
get a total I.L. of 2.9 db. I should see something like 2.1
or 2.2. I have measured the coupling cable and see .1 db,
so the cable is good. Anyone have an idea why the
The cavities were initially tuned individually and the loop
positions set for
1 db IL. They were then coupled together using a 18.5 cable
and the rods
touched up to re-establish resonance.
If the cavities had good return loss individually, there shouldn't be a need
to touch up the
What process did you go through when setting the insertion loss to the 1 dB
you were targetting? Did you optimize the coupling angle of the loops for
maximum return loss at (or near) the desired 1 dB of insertion loss?
--- Jeff WN3A
-Original Message-
I adjusted the loop positions, trying to maintain symmetry of
the curve, aiming for 1 db
on the analyzer. I didn't adjust the loops while looking at
the RL. How would I translate RL
into IL?
You can't directly translate from RL to IL or vice-versa. Here's how to
tune a pass cavity:
1.
Thanks for the detailed instructions. I understand
everything, but I'm confused about one detail.
Using this method will produce the largest RL and
consequently the lowest IL.
Well, sort of. You want the most return loss AT THE DESIRED INSERTION LOSS.
Maximizing return doesn't mean you
Jeff,
But for the purpose of this exercise, setting the loops, the
position of max RL has to be the position of min. IL? No?
That's what I said in #7. After you've tuned the cavity to resonance based
on RL, you check the IL. The frequency of the RL maxima (dip) should
coincide with the
I know this has been thrown around a bit before but I could
use a little assistance.
Go through the repeater-builder message archive on Yahoo groups. On 7/22/09
I posted a long message on the subject.
Basically I am not sure what size hex to use for the above
stated RG-58A/U and BNC and
Not from what I've seen/read. Tin/lead and even the newer RoHS-compliant
solders don't have ferrous components which is one of the biggest PIM
concerns. Besides, just about every device in the RF path has some solder
somewhere (cavity loops, integral connectors on equipment, heck even the
TLF is 800/900. TLE is UHF, TLD is highband, TLC is midband, TLB is
lowband...
-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of La Rue
Communications
Sent: Thursday, April 08, 2010 12:08 PM
To:
Anyone who is currently building analog AllStar Link
repeaters using a DMK URI already has the parts for a D-Star
repeater .. assuming your TX and RX will handle GMSK data of
your repeater.. This includes many Mastr II stations which
seem to be a large portion of the amateur repeater
RFS also has aluminum-shield versions of their standard LCF line too - the
part numbers all end in L for Lite (such as LCF78-50JL).
Aluminum-shielded cable isn't anything new. It's pretty much the standard
in CATV, and was quite common in two-way back in the day as well. Andrew,
Prodelin,
When you're pricing out 440 feet of coax, the pennies add up
to quite a
few dollars.
Depends on how you look at it. The difference becomes insignificant when
you look at the big picture. The price of 440 feet of line is a small
fraction of the total project cost once you add in
Does anyone know of a place relatively close to CT (or NYC
metro area)
that does service monitor calibrations?
Amtronix (www.amtronix.com) in NY state. Extremely reasonable, top notch
service. If shipping it is your concern, call him (Rick) and ask if he can
send you a shipping box or
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