[Repeater-Builder] Re: Notch Cavities + 600KHz Repeater = Work?

[tahrens301]

Hi Bob,

I was pretty curious about it as well, especially in
the 'early days' of this project.  Nobody seemed to
know much about the stubs.

If you are looking at the spec. analyzer & trk gen,
you see the notch.  The left side goes down deep,
then comes up on the right side of the notch.  But,
without the stubs, the right side doesn't come up
as fast as the left side went down, hence more 
insertion loss.  With the stubs, they got pulled right
up.

As far as your earlier question, the notches come
up to the 0dB point well before the other frequency.
They seem to be pretty tight.

I guess I'm still looking for an answer to the original
question.  Do the notch cavities work @600khz spacing?

I've always had the BpBr duplexers for ham stuff, & I 
guess I've gotten a bit spoiled working with 4 & 5mHz
splits!

Thanks,

Tim  W5FN



--- In Repeater-Builder@yahoogroups.com, n...@... wrote:
>
> At 8/10/2009 10:21, you wrote:
> >Hi Dcflu7x,
> >
> >It's a DB products SP-1894.  Can't get any info on it from
> >anywhere.
> >
> >Each of the 8 cans have the approx dimensions of 5" x 21".
> >A single screw-type shaft in the center, and one SO-239
> >sticking out of the top of the can.  No variable caps, or
> >anything else on the cans.  Each can has an RG-9 jumper
> >between each 'T'.  The male portion of the 'T' screws down
> >into the can.
> >
> >The 4 cans on the 147.7 side are strictly 4 cans in series.
> >The 4 cans on the 147.1 side also have an additional 'T'
> >between cans, and from that dangles a short stub.
> 
> This sounds like a modified DB-4050.  I don't understand why one side of 
> the duplexer would have additional Ts.
> 
> The specs on the DB-4050 are: notches -95 dB, passes -2.2 dB.  Sounds close 
> to what you're getting.
> 
> 
> >The stubs actually pull up the high side of the notch. Without
> >them, the cans exhibit high loss at 600khz above the notch.
> >With them, the total loss is about 2 - 2.5dB.
> 
> Bob NO6B
>

RE: [Repeater-Builder] Update, Sinclair Q-202G (Frankenstein series)

[Eric Lemmon]

Norm,

I'm glad that you're getting that duplexer working.  But, I am curious about
those parallel capacitors.  None of the factory-tuned Sinclair Q-202G
duplexers I've seen had any capacitor in parallel with the Johanson tuning
capacitors- even those made for the 2m band.  The loop assemblies for the
high-pass and low-pass cans are identical.  Perhaps the previous owner added
capacitors because the tuning caps were damaged.  Or maybe the loop
assemblies for a combiner were used in place of the correct BpBr loops.  Are
the interconnecting cables the correct length?

73, Eric Lemmon WB6FLY
 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of NORM KNAPP
Sent: Monday, August 10, 2009 6:35 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Update, Sinclair Q-202G (Frankenstein series)

  

I talked to the guy that obtained the duplxers for our club and he confirmed
my belief. Those 4 cans began life as 4 separate BpBr filters used on some
offshore communications, possibly mobile telephone or phone patch. He was
not certain. Anyway the high pass side worked great out of the box so to
speak, but the lo pass was a booger. I had to change the parralell cap
values on the tuning caps for the notches. I still don't have quite as good
a notch as I have on the high pass pair, but it works well anyway. 
73 de N5NPO 
Norm

RE: [Repeater-Builder] An advocate for a little audio compression

[Eric Lemmon]

It's funny- on the most-used local 2m repeater, we don't have a problem with
the majority of users, whose voice levels are fine.  I think compression is
necessary to cut back on a few users who 1) practically shout into the mike,
or 2) have bumped up the deviation on their radios because they think that
"more deviation is better", or 3) are using a multiband radio with
modulation still set as for HF, and don't realize that their excessive
deviation is causing distortion in the repeater.  In any case, it's a few
users who are too loud, rather than a few users who are too soft.

As a road-show sound engineer and recording-studio operator in an earlier
life, I know the benefits of seamless compression.  The primary rule is that
the static level should have no gain or compression at all, so that the
compression begins only when audio exceeds a certain level.  An audio
compressor is misapplied if it always brings up the noise level between
words.  My primary audio treatment device was a DBX 166, which also has a
noise gate.  The trick to using a noise gate properly is to set it so that
it opens at the beginning of the first syllable.  I spent a lot of time
getting the levels and timing fine-tuned so that the compression and gating
were undetectable.  It can be done with quality equipment, but good audio
processing equipment is not cheap.

I have found that it is helpful to simply advise a user that he is too loud
and needs to back away from the mike, or that he is barely audible and needs
to speak up!

73, Eric Lemmon WB6FLY


-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Paul Plack
Sent: Sunday, August 09, 2009 10:10 PM
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] An advocate for a little audio compression

  

Skipp, I generally agree, but it's not the fault of the user's voice. It's a
lack of training in mic technique, sometimes combined with audio circuits
that aren't easily user-accessible. Compression on the repeater eliminate's
the user's need to get things right at the source, and one day, he's going
to need to operate simplex.
 
I've worked with broadcast compressors for many years, and agree they could
play a useful role in repeater audio chains. But I always wanted to design
one that was a little different, and digital control of an analog signal
path seems like a good candidate.
 
Specifically, I'd like to have something like a compressor with very fast
attack and infinitely long release, immediately dropping gain as needed to
accommodate voice peaks, but not releasing until COS dropped. This would
essentially set the audio gain individually for each user at the start of a
transmission, without any ongoing compression to create the obnoxious
"pumping" artifact we all know and hate.
 
The downsides would be additional background noise before the first
syllable, and difficulty in distinguishing users with low audio from users
with inadequate signal strength. Both would feature increased background
noise as a symptom. Then again, IRLP users hand out S-meter reports from a
thousand miles away, so maybe it doesn't matter...(sigh)
 
Just running the audio gain 6-10 dB hotter into a fast limiter still allows
great disparity in perceived loudness, but at least the guys with low audio
can be heard.
 
73,
Paul, AE4KR
 

- Original Message - 
From: skipp025   
To: Repeater-Builder@yahoogroups.com
  
Sent: Sunday, August 09, 2009 9:07 PM
Subject: [Repeater-Builder] An advocate for a little audio
compression

  

...a number of operators don't seem to have voices that 
drive their radios with adequate audio...Consider 6 to 10dB of audio
compression in your repeater system...


.

 

[Repeater-Builder] Update, Sinclair Q-202G (frankenstien series)

[NORM KNAPP]

I talked to the guy that obtained the duplxers for our club and he confirmed my 
belief. Those 4 cans began life as 4 separate BpBr filters used on some 
offshore communications, possibly mobile telephone or phone patch. He was not 
certain. Anyway the high pass side worked great out of the box so to speak, but 
the lo pass was a booger. I had to change the parralell cap values on the 
tuning caps for the notches. I still don't have quite as good a notch as I have 
on the high pass pair, but it works well anyway.
73 de N5NPO
Norm

Re: [Repeater-Builder] Re: Notch Cavities + 600KHz Repeater = Work?

[no6b]

At 8/10/2009 10:21, you wrote:
>Hi Dcflu7x,
>
>It's a DB products SP-1894.  Can't get any info on it from
>anywhere.
>
>Each of the 8 cans have the approx dimensions of 5" x 21".
>A single screw-type shaft in the center, and one SO-239
>sticking out of the top of the can.  No variable caps, or
>anything else on the cans.  Each can has an RG-9 jumper
>between each 'T'.  The male portion of the 'T' screws down
>into the can.
>
>The 4 cans on the 147.7 side are strictly 4 cans in series.
>The 4 cans on the 147.1 side also have an additional 'T'
>between cans, and from that dangles a short stub.

This sounds like a modified DB-4050.  I don't understand why one side of 
the duplexer would have additional Ts.

The specs on the DB-4050 are: notches -95 dB, passes -2.2 dB.  Sounds close 
to what you're getting.


>The stubs actually pull up the high side of the notch. Without
>them, the cans exhibit high loss at 600khz above the notch.
>With them, the total loss is about 2 - 2.5dB.

Bob NO6B

Re: [Repeater-Builder] Notch Cavities + 600KHz Repeater = Work?

[no6b]

At 8/10/2009 09:07, you wrote:
>Was just curious as to if folks have
>gotten Notch cavities to work ok with a 600khz
>split.  Have 4 in Rx leg & 4 in TX leg.  According
>to the analyzer, each bank has a >90dB notch.

The big question is, what is the loss 600 kHz away from the notch?

There are some notch-only duplexers like the DB-4048 that are made for 600 
kHz spacing.  Spec'd notch depth is only 80 dB which can be a bit short, 
especially for solid-state multiplied source TXs (as opposed to tube-type 
or PLL-sourced).

Bob NO6B

Re: [Repeater-Builder] Re: An advocate for a little audio compression

[Rev. Robert P. Chrysafis]

is a desktrac repeater capable of audio compression?


- Original Message - 
From: "Laryn Lohman" 
To: 
Sent: Monday, August 10, 2009 6:41 PM
Subject: [Repeater-Builder] Re: An advocate for a little audio compression


>
> Nate, your comments about compression and bad-sounding audio coming in 
> from IRLP just goes to show, at least in part, that improperly set-up 
> compression/AGC sounds bad.
>
> For several years, I ran an Alesis 3630 on the audio coming in from IRLP 
> and feeding our local repeater transmitter.  I had it set for 3 second 
> release (the slowest it would do), fastest attack it would do, around 12db 
> of gain reduction, and around 6:1 ratio.  It sounded absolutely fine, with 
> no wierd stuff, no pumping, nothing obvious at all.  Only consistent, 
> good-level audio.  It  work and sound great.  And there's really 
> nothing inherently different betweeen audio from IRLP and audio from your 
> local receiver feeding your repeater transmitter.  As I stated in an 
> earlier post, the RC850 has internal AGC, and when properly set up, also 
> works very well with few artifacts.
>
> I think where it begins to sound bad is when the release time gets too 
> short.  That's when any background noise instantly sucks-up between words, 
> and quickly becomes ugly-sounding.
>
> Laryn K8TVZ
>
>
>
> 
>
>
>
> Yahoo! Groups Links
>
>
>
> 

Re: [Repeater-Builder] Re: Sinclair R2B12 duplexer

[Rick Szajkowski]

Google Bob Morton .. he is an x Sinclair man ..  he knows his stuff ..

he might have the info on paper ,,. if not it might still be in his
head .. as a lot of duplexers where his designs

Rick

On Mon, Aug 10, 2009 at 5:46 PM, cruizzer77 wrote:
>
>
> That's what I did first but they do at least pretend they have no info left
> on this older model duplexer. But the typical Sinclair instruction leaflet
> (some are available for other models on repeater-builder and on Sinclair's
> website) doesn't reveal such info anyway.
>
> Duplexer manufacturers in general do guard everything as jealously as they
> can.
>
> 73, Martin
>
> --- In Repeater-Builder@yahoogroups.com, "Eric Lemmon"  wrote:
>>
>> Martin,
>>
>> The best place to get that information is from the company that built it.
>> Contact Sinclair Technologies at 800-263-3275.
>>
>> 73, Eric Lemmon WB6FLY
>>
>>
>> -Original Message-
>> From: Repeater-Builder@yahoogroups.com
>> [mailto:repeater-buil...@yahoogroups.com] On Behalf Of cruizzer77
>> Sent: Saturday, August 08, 2009 12:54 AM
>> To: Repeater-Builder@yahoogroups.com
>> Subject: [Repeater-Builder] Sinclair R2B12 duplexer
>>
>>
>>
>> Does anyone have technical info (i.e. tech drawings) or inside pics of
>> these
>> duplexers? I wonder how they do the shortening as there can't be a 1/4
>> wave
>> resonator for 2m inside this 19" box...
>>
>> Regards
>> Martin
>>
>
> 

[Repeater-Builder] Re: An advocate for a little audio compression

[Laryn Lohman]

Nate, your comments about compression and bad-sounding audio coming in from 
IRLP just goes to show, at least in part, that improperly set-up 
compression/AGC sounds bad.  

For several years, I ran an Alesis 3630 on the audio coming in from IRLP and 
feeding our local repeater transmitter.  I had it set for 3 second release (the 
slowest it would do), fastest attack it would do, around 12db of gain 
reduction, and around 6:1 ratio.  It sounded absolutely fine, with no wierd 
stuff, no pumping, nothing obvious at all.  Only consistent, good-level audio.  
It  work and sound great.  And there's really nothing inherently different 
betweeen audio from IRLP and audio from your local receiver feeding your 
repeater transmitter.  As I stated in an earlier post, the RC850 has internal 
AGC, and when properly set up, also works very well with few artifacts.

I think where it begins to sound bad is when the release time gets too short.  
That's when any background noise instantly sucks-up between words, and quickly 
becomes ugly-sounding.

Laryn K8TVZ

[Repeater-Builder] Re: Sinclair R2B12 duplexer

[cruizzer77]

That's what I did first but they do at least pretend they have no info left on 
this older model duplexer. But the typical Sinclair instruction leaflet (some 
are available for other models on repeater-builder and on Sinclair's website) 
doesn't reveal such info anyway.

Duplexer manufacturers in general do guard everything as jealously as they can.

73, Martin



--- In Repeater-Builder@yahoogroups.com, "Eric Lemmon"  wrote:
>
> Martin,
> 
> The best place to get that information is from the company that built it.
> Contact Sinclair Technologies at 800-263-3275.
> 
> 73, Eric Lemmon WB6FLY
>  
> 
> -Original Message-
> From: Repeater-Builder@yahoogroups.com
> [mailto:repeater-buil...@yahoogroups.com] On Behalf Of cruizzer77
> Sent: Saturday, August 08, 2009 12:54 AM
> To: Repeater-Builder@yahoogroups.com
> Subject: [Repeater-Builder] Sinclair R2B12 duplexer
> 
>   
> 
> Does anyone have technical info (i.e. tech drawings) or inside pics of these
> duplexers? I wonder how they do the shortening as there can't be a 1/4 wave
> resonator for 2m inside this 19" box...
> 
> Regards
> Martin
>

Re: [Repeater-Builder] Maxon sm4450sc

[kerinvale]

Hi guys .thanks for the replys .The fault was I had too much length between
the radio and the ctcss decoder card .I have altered most of my repeaters to
allow the maxons to decode the signal by itself and then it controls the
transmitter by the maxon approved design with a bs170 fet .I have now
developed a interface circuit that has no relays for switching audio .and
the new design uses a 4066 audio IC to switch audio paths .It has reduced 
transmitting  delays very well .Now the repeaters seem to work almost as
soon as a signal comes in .One repeater decodes even if the signal is just
below the mute .I need to find out how that one works.All in all very happy
I have found the problem .Now I have repeaters with no ctcss breakup.   
 
Thank You,
Ian Wells,
Kerinvale Comaudio,
361 Camboon Road.Biloela.4715
Phone 0749922574 or 0409159932
www.kerinvalecomaudio.com.au
 
---Original Message---
 
From: kerinvale
Date: 11/07/2009 02:18:36
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] Maxon sm4450sc
 
Thanks for the reply 
 
Thank You,
Ian Wells,
Kerinvale Comaudio,
361 Camboon Road.Biloela.4715
Phone 0749922574 or 0409159932
www.kerinvalecomaudio.com.au
 
---Original Message---
 
From: Razvan Daniel
Date: 10/07/2009 21:57:50
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] Maxon sm4450sc
 
Hey, 
 
You can use the external card, just shield it as well as possible by
placeing it into a metal grounded case and using double or triple shieldee
coaxial condutors to link it to the radio. This wil prevent any interference
from dispurbing the useful signals. This having said, please take into
consideration that if the TX antenna is at least several meters away then
you should check the feeder, connectors and antenna reflected wave, since
this diturbance should not normlly happen in good configuration. I have also
noticed that for some reason, the internal decoder takes a wihile to react
to the carier CTSS signal. It may be a design glitch or it may be possible
that a optional delay might exist via software. I never checked. For these
reasons, I think the external card is best. 
 
Regards, 
 
Buie Daniel Razvan
RADIOCOM Bihor
004 741 133740
buie.raz...@radiotelecomunicatii.ro
www.radiotelecomunicatii.ro
 

 

--- On Fri, 7/10/09, kerinvale  wrote:


From: kerinvale 
Subject: [Repeater-Builder] Maxon sm4450sc
To: Repeater-Builder@yahoogroups.com
Date: Friday, July 10, 2009, 4:35 AM


Hi guys .I have a maxon sm4450sc  that is setup for rx ctcss decode in a
repeater and it is  decoding ctcss ok but it  only activates the call led
when the signal is over the squelch level. I am wondering is there a way
that the radio decoder can be on  all the time so even if the signal is
below the squelch the radio will activate the call led without affecting the
audio squelch level.
I tried to use ctcss external decoder card and they work great with direct
connection to the receiver audio out from the detector but as I have found
out recently with the cards outside the radio they are affected badly with
rf when the transmitter is activated if the leads are too long so I have
setup the radio to decode the ctcss and this is working well but it is slow
to activate the repeater.I am trying to set the receiver up that it will
decode as soon as the signal is present instead of it needing it to be over
the squelch level before decoding. 
 
Thank You,
Ian Wells,
Kerinvale Comaudio,
361 Camboon Road.Biloela. 4715
Phone 0749922574 or 0409159932
www.kerinvalecomaud io.com.au
 
 

 





 
 

Re: [Repeater-Builder] Hp 8921a test set

[kerinvale]

Hi guys just to finish off .the fault was the 2 amps in the input atten
After these were replaced all tested ok . 
 
Thank You,
Ian Wells,
Kerinvale Comaudio,
361 Camboon Road.Biloela.4715
Phone 0749922574 or 0409159932
www.kerinvalecomaudio.com.au
 
---Original Message---
 
From: kerinvale
Date: 31/07/2009 01:31:06
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] Hp 8921a test set
 
 I followed the unit test procedure and it failed  on filter output detector
output variable att,auto range att,duplex detector(no signal)
 
 
Thank You,
Ian Wells,
Kerinvale Comaudio,
361 Camboon Road.Biloela.4715
Phone 0749922574 or 0409159932
www.kerinvalecomaudio.com.au
 
---Original Message---
 
From: Scott Zimmerman
Date: 31/07/2009 01:06:39
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] Hp 8921a test set
 
  
Any handheld or mobile radio will work. A scanner would even be appropriate.

Scott

Scott Zimmerman
Amateur Radio Call N3XCC
474 Barnett Road
Boswell, PA 15531

kerinvale wrote:
> 
> 
> Ill try that .which is ht you refer to 
> 
> Thank You,
> Ian Wells,
> Kerinvale Comaudio,
> 361 Camboon Road.Biloela.4715
> Phone 0749922574 or 0409159932
> www.kerinvalecomaudio.com.au 
> 
> /---Original Message---/
> 
> /*From:*/ Scott Zimmerman 
> /*Date:*/ 30/07/2009 11:08:31
> /*To:*/ Repeater-Builder@yahoogroups.com 
> 
> /*Subject:*/ Re: [Repeater-Builder] Hp 8921a test set
> 
> 
> 
> Ian,
> 
> I did the same thing. (easy to do isn't it!!)
> 
> I ran the internal tests before and after the repairs and there was a
> significant difference. That's what I did to be sure it was working OK.
> I must admit, it's probably not as good as sending it somewhere for
> calibration, but on a ham budget, it works OK enough.
> 
> You could always hook your HT to the I/O port and check sensitivity then
> connect it to the duplex port and see if it's about the same. That's a
> REAL easy benchmark.
> 
> Scott
> 
> Scott Zimmerman
> Amateur Radio Call N3XCC
> 474 Barnett Road
> Boswell, PA 15531
> 
> kerinvale wrote:
> >
> >
> > I accidently hooked up my test leads to my 8921a wrong and introduced 
> high
> > Watts into the duplex out socket .Removed the a23 module and found 
> the cr203
> > And cr501 burnt out in the duplex switch .I have replaced them and 
> the unit
> > Seems to be working again .Can anyone suggest simple ways to check the
> > Duplex and ant in section to make sure there isn't any more parts 
> damaged .
> >
> > Thank You,
> > Ian Wells,
> > Kerinvale Comaudio,
> > 361 Camboon Road.Biloela.4715
> > Phone 0749922574 or 0409159932
> > www.kerinvalecomaudio.com.au  >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > --
> >
> >
> > No virus found in this incoming message.
> > Checked by AVG - www.avg.com
> > Version: 8.5.392 / Virus Database: 270.13.35/2271 - Release Date: 
> 07/29/09 18:07:00
> >
> 
> 
> 
> 
> 
> 
> 
> 
> 
> --
> 
> 
> No virus found in this incoming message.
> Checked by AVG - www.avg.com 
> Version: 8.5.392 / Virus Database: 270.13.35/2271 - Release Date: 07/29/09
18:07:00
> 

 
 

Re: [Repeater-Builder] SM50 440 mod

[k7pfj]

Yes they will play nice down there. I have had t many to count as links 
Full-Duplex and they will play nice to the 430Mhz without any modification 
other than the hacked software. 



Mike Mullarkey 



- Original Message - 
From: "tonyn2mft"  
To: Repeater-Builder@yahoogroups.com 
Sent: Monday, August 10, 2009 4:47:15 AM GMT -07:00 US/Canada Mountain 
Subject: [Repeater-Builder] SM50 440 mod 

  




Trying to get a UHF SM50 M44DCG20A2AAA down to 440. 

Already tried the shift method without success. Searched Google high and low 
with little success. There was a few threads on the boards about moving this 
down. Dropped and few emails with out a return. 

I've read on Batlabs on moving the SM50 to cover the entire band limits on VHF. 
Nothing on UHF. 

Can this radio go down to 440? Any help would move this project off my bench 
and desk. 

Thanks. 

Tony 

Re: [Repeater-Builder] Re: Notch Cavities + 600KHz Repeater = Work?

[DCFluX]

I've actually seen that before on a Wacom.  Go with silver bearing
solder if you have it.

On Mon, Aug 10, 2009 at 11:19 AM, tahrens301 wrote:
> Hi Ralph,
>
> No, they were 10" as came from the factory for 166 mhz,
> so it didn't look like they were cut for anything
> in particular.
>
> DCflux - I started to do what  you suggested... sounded
> like something else to try.  Took the link out of the
> last can & the loop wasn't soldered to the PL259 connection.
> Only a solder blob on the end of the pin.  I could push
> on the link & it would freely move on the pin.  NOT GOOD!
>
> Think I'll pull them all out & have a look - I found one
> like this earlier in the other side.  Guess it was built
> on a Monday! haha
>
> Thanks,
>
> Tim
>
>
>
>
>
> 
>
>
>
> Yahoo! Groups Links
>
>
>
>

[Repeater-Builder] Re: Notch Cavities + 600KHz Repeater = Work?

[tahrens301]

Hi Ralph,

No, they were 10" as came from the factory for 166 mhz,
so it didn't look like they were cut for anything
in particular.

DCflux - I started to do what  you suggested... sounded
like something else to try.  Took the link out of the
last can & the loop wasn't soldered to the PL259 connection.
Only a solder blob on the end of the pin.  I could push
on the link & it would freely move on the pin.  NOT GOOD!

Think I'll pull them all out & have a look - I found one
like this earlier in the other side.  Guess it was built
on a Monday! haha

Thanks,

Tim

Re: [Repeater-Builder] Re: Notch Cavities + 600KHz Repeater = Work?

[Ralph Mowery]

--- On Mon, 8/10/09, tahrens301  wrote:

> From: tahrens301 
> Subject: [Repeater-Builder] Re: Notch Cavities + 600KHz Repeater = Work?
> To: Repeater-Builder@yahoogroups.com
> Date: Monday, August 10, 2009, 1:21 PM
> Hi Dcflu7x,
> 
> It's a DB products SP-1894.  Can't get any info on it
> from
> anywhere.
> 
> Each of the 8 cans have the approx dimensions of 5" x 21".
> A single screw-type shaft in the center, and one SO-239
> sticking out of the top of the can.  No variable caps,
> or 
> anything else on the cans.  Each can has an RG-9
> jumper
> between each 'T'.  The male portion of the 'T' screws
> down
> into the can.
> 
> The 4 cans on the 147.7 side are strictly 4 cans in
> series.
> The 4 cans on the 147.1 side also have an additional 'T'
> between cans, and from that dangles a short stub.
> 
> The stubs actually pull up the high side of the notch.
> Without
> them, the cans exhibit high loss at 600khz above the
> notch.
> With them, the total loss is about 2 - 2.5dB.
> 
> The duplexer was originally in the 166 range, then pulled
> down
> to the 154 range, which was what they were set for when I
> got them.
> 
>


Did you change the coax lengths to match the change in frequency ?




  

Re: [Repeater-Builder] Re: 2M Vertical Dipoles

[AJ]

Hmm, that would make sense... Back to the drawing board :)

On Mon, Aug 10, 2009 at 11:15 AM, Kevin Custer  wrote:

>
>
> Paul Plack wrote:
>
> If you mount the array on a non-conductive pole, won't you then have to
> model the effects of interaction with the outside of the coax shields of the
> feedline harness that would normally be insignificant when attached to the
> side of a conductive pole?
>
>
>
> Be careful hereSome dipole arrays, like the cushcraft, requires a
> metallic support pole to obtain/maintain the 50 ohm feedpoint impedance.
>
> Kevin
>
> 
>

Re: [Repeater-Builder] Re: Notch Cavities + 600KHz Repeater = Work?

[DCFluX]

Ok, if they are the type with the variable coupling loop you should
have 2 coupling loop holes per cavity, just one has a round hole
cover. If so take 2 cavities and transplant a coupling loop to one of
them to make 1 band pass cavity. Make another one for the RX side

Place the band pass cavities closest to the repeater in each leg. So
you have 1 band pass and 2 rejects and then the tee.

If that doesn't work you might try converting them to BpBr. This would
be done by adding a very high quality piston trimmer such as a
johansen cap to the coupling loop, in series with the grounded end. Or
a BNC jack going to a piece of coax that can be trimmed to form a
gimmic capacitor.

I like to salvage the capacitor from surplus Mastr 2 ICOMs that are
EC. But those have to be soldered in and I'm not sure what material DB
cans use on the rotatable whosis.

The inner cavity jumpers should be 1/4 wavelength electrically, so you
have to calculate velocity factor of your cables.

4 cavities should give you 80-85dB. and I like to use a circulator as
the tee to the antenna which brings it up to the 100dB range.. But if
you don't have one, try just 4 cavities and if you still have desense
try 6.




On Mon, Aug 10, 2009 at 10:21 AM, tahrens301 wrote:
> Hi Dcflu7x,
>
> It's a DB products SP-1894.  Can't get any info on it from
> anywhere.
>
> Each of the 8 cans have the approx dimensions of 5" x 21".
> A single screw-type shaft in the center, and one SO-239
> sticking out of the top of the can.  No variable caps, or
> anything else on the cans.  Each can has an RG-9 jumper
> between each 'T'.  The male portion of the 'T' screws down
> into the can.
>
> The 4 cans on the 147.7 side are strictly 4 cans in series.
> The 4 cans on the 147.1 side also have an additional 'T'
> between cans, and from that dangles a short stub.
>
> The stubs actually pull up the high side of the notch. Without
> them, the cans exhibit high loss at 600khz above the notch.
> With them, the total loss is about 2 - 2.5dB.
>
> The duplexer was originally in the 166 range, then pulled down
> to the 154 range, which was what they were set for when I got them.
>
> Tuning:  First I used the spectrum analyzer with tracking generator
> to move each notch on top of each other at the desired frequency.
> Next, I used my service monitor to generate a +10dBm signal
> which I fed through each set of 4 cans.  On the opposite side, I
> hooked up the spectrum analyzer & tuned out the signal.  It told
> me it was between -92 & -95 dB on each set of cans.  I also put
> a 50 ohm load on the port that I was not testing.
>
> I think they are tweaked as good as they can be.
>
> Thanks,
>
> Tim  W5FN
>
>
>
>
> --- In Repeater-Builder@yahoogroups.com, DCFluX  wrote:
>>
>> Can you tell us more about the model of your duplexer?
>>
>> When you say notch is it:
>>
>> A. Flat pack mobile style notch only duplexer with a 3MHz minimum split.
>> B. Wacom BpBr cavites such as WP-639.
>> C. Motorola style notch only small cans.
>>
>> Also if you have a VHF circulator you can replace the tee between the
>> 2 sides of the duplexer and antenna for an additional 20dB of
>> isolation.
>>
>>
>> On Mon, Aug 10, 2009 at 9:07 AM, tahrens301 wrote:
>> > Was just curious as to if folks have
>> > gotten Notch cavities to work ok with a 600khz
>> > split.  Have 4 in Rx leg & 4 in TX leg.  According
>> > to the analyzer, each bank has a >90dB notch.
>> > Double shielded cable throughout (RG-9).
>> >
>> > Just about pulled all my hair out over the last
>> > couple of weeks, and still have desense issues.
>> > Even tried another repeater, just to see if it
>> > was still there, & yep it is. (was actually a
>> > bit worse than the Quantar, but it uses cheesy
>> > cables for RX (TKR-720)).
>> >
>> > Did find something interesting inside the Quantar
>> > tho, the RX cable that screws into the RX filter
>> > housing had a problem.  They use a crimped Mini-UHF,
>> > and the section that got crimped actually rotated
>> > freely around the piece that has the center conductor
>> > in it.  Nice rotatable cable, but don't think that
>> > it was intended to do that!  Soldered the two together.
>> >
>> > Thanks,
>> >
>> > Tim  W5FN
>> >
>> >
>> >
>> > 
>> >
>> >
>> >
>> > Yahoo! Groups Links
>> >
>> >
>> >
>> >
>>
>
>
>
>
> 
>
>
>
> Yahoo! Groups Links
>
>
>
>

[Repeater-Builder] Re: Notch Cavities + 600KHz Repeater = Work?

[tahrens301]

Hi Dcflu7x,

It's a DB products SP-1894.  Can't get any info on it from
anywhere.

Each of the 8 cans have the approx dimensions of 5" x 21".
A single screw-type shaft in the center, and one SO-239
sticking out of the top of the can.  No variable caps, or 
anything else on the cans.  Each can has an RG-9 jumper
between each 'T'.  The male portion of the 'T' screws down
into the can.

The 4 cans on the 147.7 side are strictly 4 cans in series.
The 4 cans on the 147.1 side also have an additional 'T'
between cans, and from that dangles a short stub.

The stubs actually pull up the high side of the notch. Without
them, the cans exhibit high loss at 600khz above the notch.
With them, the total loss is about 2 - 2.5dB.

The duplexer was originally in the 166 range, then pulled down
to the 154 range, which was what they were set for when I got them.

Tuning:  First I used the spectrum analyzer with tracking generator
to move each notch on top of each other at the desired frequency.
Next, I used my service monitor to generate a +10dBm signal
which I fed through each set of 4 cans.  On the opposite side, I
hooked up the spectrum analyzer & tuned out the signal.  It told
me it was between -92 & -95 dB on each set of cans.  I also put
a 50 ohm load on the port that I was not testing.

I think they are tweaked as good as they can be.

Thanks,

Tim  W5FN




--- In Repeater-Builder@yahoogroups.com, DCFluX  wrote:
>
> Can you tell us more about the model of your duplexer?
> 
> When you say notch is it:
> 
> A. Flat pack mobile style notch only duplexer with a 3MHz minimum split.
> B. Wacom BpBr cavites such as WP-639.
> C. Motorola style notch only small cans.
> 
> Also if you have a VHF circulator you can replace the tee between the
> 2 sides of the duplexer and antenna for an additional 20dB of
> isolation.
> 
> 
> On Mon, Aug 10, 2009 at 9:07 AM, tahrens301 wrote:
> > Was just curious as to if folks have
> > gotten Notch cavities to work ok with a 600khz
> > split.  Have 4 in Rx leg & 4 in TX leg.  According
> > to the analyzer, each bank has a >90dB notch.
> > Double shielded cable throughout (RG-9).
> >
> > Just about pulled all my hair out over the last
> > couple of weeks, and still have desense issues.
> > Even tried another repeater, just to see if it
> > was still there, & yep it is. (was actually a
> > bit worse than the Quantar, but it uses cheesy
> > cables for RX (TKR-720)).
> >
> > Did find something interesting inside the Quantar
> > tho, the RX cable that screws into the RX filter
> > housing had a problem.  They use a crimped Mini-UHF,
> > and the section that got crimped actually rotated
> > freely around the piece that has the center conductor
> > in it.  Nice rotatable cable, but don't think that
> > it was intended to do that!  Soldered the two together.
> >
> > Thanks,
> >
> > Tim  W5FN
> >
> >
> >
> > 
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
>

Re: [Repeater-Builder] Micor cos question

[Nick W7NIK]

Thanks Kevin , That mobile note threw me off . I did see that mod. I will give 
that a try thanks again. Your mods are very helpful.
 Nick 
w7nik 
775-626-7605 
Web site-- http://geocities.com/w7...@sbcglobal.net/ 
"When all else fails . Amateur Radio." 





From: Kevin Custer 
To: Repeater-Builder@yahoogroups.com
Sent: Monday, August 10, 2009 10:13:14 AM
Subject: Re: [Repeater-Builder] Micor cos question

  
Nick W7NIK wrote: 
I did only the one mod which was .
>9.6v to a 10k resistor to the base, emitter went to ground, collector to the 
>controller. This mod was on the better duplexing for a micor  station on 
>repeater builder site.
That part of the modification is not intended to drive a controller - it is 
intended to drive internal cards after doing the modifications suggested for 
better muting.

You simply need a logic inverter:
http://www.repeater -builder. com/pix/cosswitc h.gif

Disregard the (mobile only) note - this circuit is what you need to drive a 
controller - whether or not you have a Mobile or Station.

Kevin

Re: [Repeater-Builder] Re: 2M Vertical Dipoles

[Kevin Custer]

Paul Plack wrote:



If you mount the array on a non-conductive pole, won't you then have 
to model the effects of interaction with the outside of the coax 
shields of the feedline harness that would normally be insignificant 
when attached to the side of a conductive pole?



Be careful hereSome dipole arrays, like the cushcraft, requires 
a metallic support pole to obtain/maintain the 50 ohm feedpoint impedance.


Kevin

Re: [Repeater-Builder] Micor cos question

[Kevin Custer]

Nick W7NIK wrote:



I did only the one mod which was .
9.6v to a 10k resistor to the base, emitter went to ground, collector 
to the controller. This mod was on the better duplexing for a micor  
station on repeater builder site.


That part of the modification is not intended to drive a controller - it 
is intended to drive internal cards after doing the modifications 
suggested for better muting.


You simply need a logic inverter:
http://www.repeater-builder.com/pix/cosswitch.gif

Disregard the (mobile only) note - this circuit is what you need to 
drive a controller - whether or not you have a Mobile or Station.


Kevin

Re: [Repeater-Builder] Micor cos question

[Nick W7NIK]

I might have to add 12 volts into a 10k to the collector. Thanks to a friend in 
our club , he suggested to use the NHRC cas inverter . I did not want to that 
with out direction. I don't smoke anymore ::))
 Nick 
w7nik 
775-626-7605 
Web site-- http://geocities.com/w7...@sbcglobal.net/ 
"When all else fails . Amateur Radio." 





From: Nick W7NIK 
To: Repeater-Builder@yahoogroups.com
Sent: Monday, August 10, 2009 9:17:11 AM
Subject: Re: [Repeater-Builder] Micor cos question

  
I did only the one mod which was .
9.6v to a 10k resistor to the base, emitter went to ground, collector to the 
controller. This mod was on the better duplexing for a micor  station on 
repeater builder site.

 Nick 
w7nik 
775-626-7605 
Web site-- http://geocities. com/w7nik@ sbcglobal. net/ 
"When all else fails . Amateur Radio." 





From: Chuck Kelsey 
To: Repeater-Builder@ yahoogroups. com
Sent: Monday, August 10, 2009 4:13:32 AM
Subject: Re: [Repeater-Builder] Micor cos question

  
Did you put a pull-up resistor on the collector of the transistor?

Chuck
WB2EDV

- Original Message - 
From: "Nick" 
To: 
Sent: Monday, August 10, 2009 1:32 AM
Subject: [Repeater-Builder] Micor cos question

>I have a micor Station , I did the mod for the cos on the audio sq board . 
>I have 9.6v no signal , with signal 0 volts. I need o volts no signal and 5 
>volts or more for signal. I did the invert logic mod , with the 10 k npn 
>2n transiter not enough voltage less than 1 volt. Any Ideas ?
>
>
>
>
>  - - --
>
>
>
> Yahoo! Groups Links
>
>
>

Re: [Repeater-Builder] Re: 2M Vertical Dipoles

[Paul Plack]

If you mount the array on a non-conductive pole, won't you then have to model 
the effects of interaction with the outside of the coax shields of the feedline 
harness that would normally be insignificant when attached to the side of a 
conductive pole?

  - Original Message - 
  From: AJ 
  To: Repeater-Builder@yahoogroups.com 
  Sent: Monday, August 10, 2009 9:27 AM
  Subject: Re: [Repeater-Builder] Re: 2M Vertical Dipoles



  On this same topic of the mast-less Antennex/Laird dipole arrays, has anyone 
attempted to top mount these from a fiberglass mast to minimize interaction 
with the normal steel pole? I have quite a few surplus fiberglass poles left 
that would likely work, even for side mounting on 1/2 wave spacing from the 
tower...



  

Re: [Repeater-Builder] Notch Cavities + 600KHz Repeater = Work?

[DCFluX]

Can you tell us more about the model of your duplexer?

When you say notch is it:

A. Flat pack mobile style notch only duplexer with a 3MHz minimum split.
B. Wacom BpBr cavites such as WP-639.
C. Motorola style notch only small cans.

Also if you have a VHF circulator you can replace the tee between the
2 sides of the duplexer and antenna for an additional 20dB of
isolation.


On Mon, Aug 10, 2009 at 9:07 AM, tahrens301 wrote:
> Was just curious as to if folks have
> gotten Notch cavities to work ok with a 600khz
> split.  Have 4 in Rx leg & 4 in TX leg.  According
> to the analyzer, each bank has a >90dB notch.
> Double shielded cable throughout (RG-9).
>
> Just about pulled all my hair out over the last
> couple of weeks, and still have desense issues.
> Even tried another repeater, just to see if it
> was still there, & yep it is. (was actually a
> bit worse than the Quantar, but it uses cheesy
> cables for RX (TKR-720)).
>
> Did find something interesting inside the Quantar
> tho, the RX cable that screws into the RX filter
> housing had a problem.  They use a crimped Mini-UHF,
> and the section that got crimped actually rotated
> freely around the piece that has the center conductor
> in it.  Nice rotatable cable, but don't think that
> it was intended to do that!  Soldered the two together.
>
> Thanks,
>
> Tim  W5FN
>
>
>
> 
>
>
>
> Yahoo! Groups Links
>
>
>
>

Re: [Repeater-Builder] Micor cos question

[Nick W7NIK]

I did only the one mod which was .
9.6v to a 10k resistor to the base, emitter went to ground, collector to the 
controller. This mod was on the better duplexing for a micor  station on 
repeater builder site.

 Nick 
w7nik 
775-626-7605 
Web site-- http://geocities.com/w7...@sbcglobal.net/ 
"When all else fails . Amateur Radio." 





From: Chuck Kelsey 
To: Repeater-Builder@yahoogroups.com
Sent: Monday, August 10, 2009 4:13:32 AM
Subject: Re: [Repeater-Builder] Micor cos question

  
Did you put a pull-up resistor on the collector of the transistor?

Chuck
WB2EDV

- Original Message - 
From: "Nick" 
To: 
Sent: Monday, August 10, 2009 1:32 AM
Subject: [Repeater-Builder] Micor cos question

>I have a micor Station , I did the mod for the cos on the audio sq board . 
>I have 9.6v no signal , with signal 0 volts. I need o volts no signal and 5 
>volts or more for signal. I did the invert logic mod , with the 10 k npn 
>2n transiter not enough voltage less than 1 volt. Any Ideas ?
>
>
>
>
>  - - --
>
>
>
> Yahoo! Groups Links
>
>
>

Re: [Repeater-Builder] SM50 440 mod

[Cort Buffington]

I used the batlabs article:

http://www.batlabs.com/sm50.html

and modified my codeplug file to make mine go down to 438 It works  
pretty good down to 440, but it starts dropping off pretty quickly  
below that.

On Aug 10, 2009, at 5:47 AM, tonyn2mft wrote:

> Trying to get a UHF SM50 M44DCG20A2AAA down to 440.
>
> Already tried the shift method without success. Searched Google high  
> and low with little success. There was a few threads on the boards  
> about moving this down. Dropped and few emails with out a return.
>
> I've read on Batlabs on moving the SM50 to cover the entire band  
> limits on VHF. Nothing on UHF.
>
> Can this radio go down to 440? Any help would move this project off  
> my bench and desk.
>
> Thanks.
>
> Tony
>
>
> 

--
Cort Buffington
H: +1-785-838-3034
M: +1-785-865-7206










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[Repeater-Builder] Notch Cavities + 600KHz Repeater = Work?

[tahrens301]

Was just curious as to if folks have
gotten Notch cavities to work ok with a 600khz
split.  Have 4 in Rx leg & 4 in TX leg.  According
to the analyzer, each bank has a >90dB notch.
Double shielded cable throughout (RG-9).

Just about pulled all my hair out over the last
couple of weeks, and still have desense issues.  
Even tried another repeater, just to see if it 
was still there, & yep it is. (was actually a
bit worse than the Quantar, but it uses cheesy
cables for RX (TKR-720)).

Did find something interesting inside the Quantar
tho, the RX cable that screws into the RX filter
housing had a problem.  They use a crimped Mini-UHF,
and the section that got crimped actually rotated
freely around the piece that has the center conductor
in it.  Nice rotatable cable, but don't think that
it was intended to do that!  Soldered the two together.

Thanks,

Tim  W5FN

[Repeater-Builder] SM50 440 mod

[tonyn2mft]

Trying to get a UHF SM50 M44DCG20A2AAA down to 440.

Already tried the shift method without success.  Searched Google high and low 
with little success. There was a few threads on the boards about moving this 
down. Dropped and few emails with out a return.

I've read on Batlabs on moving the SM50 to cover the entire band limits on VHF. 
 Nothing on UHF.  

Can this radio go down to 440?  Any help would move this project off my bench 
and desk.

Thanks.

Tony 

Re: [Repeater-Builder] Re: 2M Vertical Dipoles

[AJ]

On this same topic of the mast-less Antennex/Laird dipole arrays, has anyone
attempted to top mount these from a fiberglass mast to minimize interaction
with the normal steel pole? I have quite a few surplus fiberglass poles left
that would likely work, even for side mounting on 1/2 wave spacing from the
tower...

On that same note, does anyone have construction plans for a dipole array
(not necessarily folded dipoles)? I remember seeing a set of plans somewhere
quite a while ago - we're thinking of constructing one but encasing the
dipoles in fiberglass or PVC to try to protect from the weather and debris
at our site (top of a large farm field)...

73,
AJ, K6LOR

On Mon, Aug 10, 2009 at 9:17 AM, Paul Dumdie  wrote:

>
>
>
> If you want Laird / Antenex does make a 2 and 4 dipole array for the 2
> meter band the part number is YDA1362 for a 2 dipole 136-150 antenna and
> YDA1364 for the 4 dipole antenna. They don't come with a mast pipe like the
> cushcraft antennas from long ago. They have a YDA2004 for 200-225 MHZ
> and a YDA4304 for 430-450 MHZ. They all come with the dipoles and the
> harness and you supply the mast pipe or it can be ordered with the antenna.
>
> I am ordering one of the YDA1362 to check out how they work.
>
> Now that amateur line of Cushcraft has been absorbed by MFJ it will be
> interesting to see what happens to the line of Cushcraft antennas.
>
> Paul R. Dumdie Jr. "73"
> W9DWP/R IRLP-NODE-4455
> 443.025/2A 145.270/1B/1Z/NAC-293
> ARC-Radio-8 KCARES KCAPS
> HERD546 EX WB9QWZ
> WQGG738-462.725 AAR5CU/T
> www.riflesandradios.com
> www.theherd.com
> 
>

[Repeater-Builder] Re: 2M Vertical Dipoles

[Paul Dumdie]

If you want Laird / Antenex does make a 2 and 4 dipole array for the 2 meter 
band the part number is YDA1362 for a 2 dipole 136-150 antenna and YDA1364 for 
the 4 dipole antenna. They don't come with a mast pipe like the cushcraft 
antennas from long ago. They have a YDA2004 for 200-225 MHZ
and a YDA4304 for 430-450 MHZ. They all come with the dipoles and the harness 
and you supply the mast pipe or it can be ordered with the antenna.

I am ordering one of the YDA1362 to check out how they work. 

Now that amateur line of Cushcraft has been absorbed by MFJ it will be 
interesting to see what happens to the line of Cushcraft antennas. 



Paul R. Dumdie Jr. "73"
W9DWP/R IRLP-NODE-4455
443.025/2A 145.270/1B/1Z/NAC-293
ARC-Radio-8  KCARES  KCAPS 
HERD546  EX WB9QWZ
WQGG738-462.725 AAR5CU/T
www.riflesandradios.com
www.theherd.com

[Repeater-Builder] Re: Replacement Caps. for Motorola Micor Pwr supplies

[Greg Beat]

CDE Capacitors:  http://www.cde.com/

All major distributors (Mouser, DigiKey, Allied, Newark, Future, Arrow) carry 
these USA made products -- 

BUT no specific distributor based in Hawaii.

Need mounting hardware for the new capacitor styles?

http://www.cde.com/catalogs/hardware.pdf

Join CDE's Laird Macomber for a 15 minute webcast demystifying capacitor 
selection with these highpoints:

  a.. Realistic performance expectations 
  b.. Typical power electronics applications 
  c.. Capacitor selection keys for success 
  d.. CDE expected life calculator for optimizing your design. 
  e.. Review of screw terminal, flatpack and snap-in capacitor choices.
Enjoy the experience of updating your bus capacitor design skills with this web 
cast.

http://www.eetechbrief.com/login.php?event_id=77&pro=hearst

Re: [Repeater-Builder] Micor cos question

[Chuck Kelsey]

Did you put a pull-up resistor on the collector of the transistor?

Chuck
WB2EDV




- Original Message - 
From: "Nick" 
To: 
Sent: Monday, August 10, 2009 1:32 AM
Subject: [Repeater-Builder] Micor cos question


>I have a micor Station , I did  the mod for the cos on the audio sq board . 
>I have 9.6v no signal , with signal 0 volts. I need o volts no signal and 5 
>volts or more for signal. I did the invert logic mod , with the 10 k npn 
>2n transiter not enough voltage less than 1 volt. Any Ideas ?
>
>
>
>
> 
>
>
>
> Yahoo! Groups Links
>
>
>