Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)

[Gmail - Kevin, Natalia, Stacey & Rochelle]

Hi,
Is there a point inside the Mitrek that one can take the audio out to the 
controller (in this case a Link-Comm RLC-2A)? A low band Mitrek (33Mhz)
I have downloaded the information from"Lou's Mitrek Repeater Conversion" and a 
couple of others which mention a schematic for emphasis before going into the 
controller. Taking the audio out on pin 11.
I would like to leave this out if possible and feed directly?

Regards and Merry Christmas

Kev.


  - Original Message - 
  From: Kevin Custer 
  To: Repeater-Builder@yahoogroups.com 
  Sent: Sunday, December 21, 2008 2:40 PM
  Subject: Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 
(WAS: Holiday Special...)


  Eric Lemmon wrote:
  > Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081,
  > 136-146 MHz) is still available from Motorola Parts. That one is part
  > 2480032A07, the violet coil in L1, for $ 4.15.
  >
  > The only option may be to tack on some extra wire to the existing coils.
  > Although modifying the tuning screws may work, I suspect the Q will suffer.
  Eric,

  I would think a coil retro like what I make available for the MICOR will 
  also work in the Mitrek. This approach would be way better than tacking 
  some added wire onto the existing coil or modifying the screws in which 
  I know that is a bad idea. Is there something special about the Mitrek 
  front-end that you believe would prohibit such a conversion? It's been 
  a while since I messed with the Mitrek but I don't remember anything 
  that would prohibit the correct length coil to be installed...

  Kevin


   

Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)

[Kevin Custer]

Hi Eric,
> Kevin,
>
> Other than being physically smaller, I don't know of any helical resonator
> design issues that preclude your Micor mod from being adapted to the Mitrek.


Oh okay   good - - I was unsure if there was something I was 
missing; which could easily be the case.

Thanks,
Kevin

Re: [Repeater-Builder] RE: What Have I got and can I get information about it.

[Milt]

The question is frequency stability for fixed stations.  If the unit is 
operated as built (minus the phone patch) vs the possible use of an external 
amplifier as mentioned in the original post.  Just because the portable on 
which the unit is based is type accepted for portable use, the use of the same 
radio in a fixed station configuration could possibly fall under a different 
set of standards.  Be sure to consult the appropriate sections of the current 
version of Part 95.

MIlt
N3LTQ
  
  - Original Message - 
  From: Craig W Clark 
  To: Repeater-Builder@yahoogroups.com 
  Sent: Thursday, December 18, 2008 2:35 PM
  Subject: RE: [Repeater-Builder] RE: What Have I got and can I get information 
about it.


  Huh? Since when is a GP300 not type accepted for GMRS? News to me, but I have 
been wrong before. (once!)



  -Original Message-
  From: Repeater-Builder@yahoogroups.com 
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Milt
  Sent: Thursday, December 18, 2008 2:12 PM
  To: Repeater-Builder@yahoogroups.com
  Subject: Re: [Repeater-Builder] RE: What Have I got and can I get information 
about it.



  Rick,



  The Systel was a 2 watt repeater with a telephone interconnect designed for 
small on-site systems.  I doubt that it would be type accepted for GMRS as it 
was based on one or more series of portables (HT-90 and/or GP300).  Of course 
the phone patch would not be usable on GMRS either.



  MIlt

  N3LTQ





- Original Message - 

From: Rick Beatty 

To: Repeater-Builder@yahoogroups.com 

Sent: Thursday, December 18, 2008 12:37 AM

Subject: [Repeater-Builder] RE: What Have I got and can I get information 
about it.



I recently was given a SYSTEL unit made by Motorola, on 464.../469... with 
duplexer and looks to be a repeater, with low level output (2w or so). Would be 
great for remote work on GMRS, does anyone on the group have data/information 
on this little cutie?

Also I am looking for a schematic for an amplifier used with the portable. 
a UHF with the number N1275a? 

thanks in advance -- 

Rick 



   

RE: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)

[Eric Lemmon]

Kevin,

Other than being physically smaller, I don't know of any helical resonator
design issues that preclude your Micor mod from being adapted to the Mitrek.
I am modifying some low-band Mitreks for 6m duty, but all that takes is a
handful of capacitors.  I have yet to address converting a high-band Mitrek
to 2m, so I have no idea what issues may arise.

73, Eric Lemmon WB6FLY


-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Kevin Custer
Sent: Saturday, December 20, 2008 5:41 PM
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1
(WAS: Holiday Special...)

Eric Lemmon wrote:
> Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081,
> 136-146 MHz) is still available from Motorola Parts. That one is part
> 2480032A07, the violet coil in L1, for $ 4.15.
>
> The only option may be to tack on some extra wire to the existing coils.
> Although modifying the tuning screws may work, I suspect the Q will
suffer.
Eric,

I would think a coil retro like what I make available for the MICOR will 
also work in the Mitrek. This approach would be way better than tacking 
some added wire onto the existing coil or modifying the screws in which 
I know that is a bad idea. Is there something special about the Mitrek 
front-end that you believe would prohibit such a conversion? It's been 
a while since I messed with the Mitrek but I don't remember anything 
that would prohibit the correct length coil to be installed...

Kevin


 

Re: [Repeater-Builder] VXR 7000 with desense

[no6b]

At 12/18/2008 10:02, you wrote:
>Hi Rick -- I am new to the group so I have not seen all of the posts with 
>regards to your problem on the 7000. However, one thing that
>you may want to check is whether the PL is feeding back into the RX from 
>the TX, if the tones are the same. I have seen this several
>times in the past on different machines and it is always annoying.
>
>Don't assume that just because you can run PL in and out that it will be 
>able to run the same tone.

Why not?  If something is mixing the output back to the input, normally 
you'd want to find & eliminate it since it's necessarily causing 
desense.  Running different or "split tones", can serve to cover up the 
problem if it's external to your equipment and out of your 
control.  However, most ham transceivers are not capable of split tone 
operation.

Bob NO6B

Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)

[Kevin Custer]

Eric Lemmon wrote:
> Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081,
> 136-146 MHz) is still available from Motorola Parts.  That one is part
> 2480032A07, the violet coil in L1, for $ 4.15.
>
> The only option may be to tack on some extra wire to the existing coils.
> Although modifying the tuning screws may work, I suspect the Q will suffer.
Eric,

I would think a coil retro like what I make available for the MICOR will 
also work in the Mitrek.  This approach would be way better than tacking 
some added wire onto the existing coil or modifying the screws in which 
I know that is a bad idea.  Is there something special about the Mitrek 
front-end that you believe would prohibit such a conversion?  It's been 
a while since I messed with the Mitrek but I don't remember anything 
that would prohibit the correct length coil to be installed...

Kevin

Re: [Repeater-Builder] UHF Micor Station

[Kevin Custer]

Terry wrote:
> I'm reassembling a UHF Micor station. I have a Audio/squelch
> #TRN6006A. Is this the correct board? 

Yes - usually.
> There is no audio amp in the
> chassis either. Does it use one from a VHF or UHF Mobile??

Most of the audio amp is on the A&S Board, but the pass transistor 
(power amplifier) assembly is on a hunk of aluminum, and yes this 
assembly (TLN4290B) can be stolen from a mobile and used in the 
station.  The hunk of aluminum is anodized (coated).  The anodizing 
doesn't conduct electricity.  This allows the transistors to be 
assembled to the heatsink without an insulating washer.  While you don't 
need to remove the transistors for remounting the assembly into the 
station, you should be careful with it as not to scratch this coating 
off when handling it.

Kevin Custer

[Repeater-Builder] UHF Micor Station

[Terry]

I'm reassembling a UHF Micor station. I have a Audio/squelch
#TRN6006A. Is this the correct board? There is no audio amp in the
chassis either. Does it use one from a VHF or UHF Mobile??

Thx  WX3M

Re: [Repeater-Builder] Doug Hall 4RV Voter

[Mike Dietrich]

Yes Kevin,
I am interested, contact me off list to discuss.
Mike  KB5FLX
m.dietr...@peoplepc.com
---
  - Original Message - 
  From: Kevin Berlen, K9HX 
  To: Repeater-Builder@yahoogroups.com 
  Cc: repeat...@yahoogroups.com 
  Sent: Saturday, December 20, 2008 1:47 PM
  Subject: [Repeater-Builder] Doug Hall 4RV Voter


  I have available a DHE 4RV 4 receiver voter system. Please note that 
  this is an
  older generation than the 4RV/2 which is currently being produced. This system
  consists of a 4RV voter, a VCM, and power supply in a 19 inch rack 
  mount. It was
  removed from a site that was decommissioned and was not hooked up, so I do not
  know the operational status. If interested, please e-mail me direct, 
  off list. I would
  prefer a trade, but all offers considered. Thanks and 73,

  Kevin, K9HX



   

RE: [Repeater-Builder] RE: What Have I got and can I get information about it.

[Eric Lemmon]

You're not wrong this time.  A UHF GP300 radio with the FCC ID of either
ABZ99FT4010 or ABZ99FT4011 is approved for Part 95- but only for 16K0F3E
emissions.  GMRS yes, FRS no.

Moving on to the SYSTEL question, I just discovered that the manual is still
available from Motorola Parts.  It is manual 6882446W01, for about $17.

73, Eric Lemmon WB6FLY
 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Craig W Clark
Sent: Thursday, December 18, 2008 11:36 AM
To: Repeater-Builder@yahoogroups.com
Subject: RE: [Repeater-Builder] RE: What Have I got and can I get
information about it.

Huh? Since when is a GP300 not type accepted for GMRS? News to me, but I
have been wrong before. (once!)

 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Milt
Sent: Thursday, December 18, 2008 2:12 PM
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] RE: What Have I got and can I get
information about it.

 

Rick,

 

The Systel was a 2 watt repeater with a telephone interconnect designed for
small on-site systems.  I doubt that it would be type accepted for GMRS as
it was based on one or more series of portables (HT-90 and/or GP300).  Of
course the phone patch would not be usable on GMRS either.

 

MIlt

N3LTQ

 

 

- Original Message - 

From: Rick Beatty   

To: Repeater-Builder@yahoogroups.com
  

Sent: Thursday, December 18, 2008 12:37 AM

Subject: [Repeater-Builder] RE: What Have I got and can I get
information about it.

 

I recently was given a SYSTEL unit made by Motorola, on
464.../469... with duplexer and looks to be a repeater, with low level
output (2w or so). Would be great for remote work on GMRS, does anyone on
the group have data/information on this little cutie?

Also I am looking for a schematic for an amplifier used with the
portable. a UHF with the number N1275a? 

thanks in advance -- 

Rick 



 

[Repeater-Builder] Doug Hall 4RV Voter

[Kevin Berlen, K9HX]

I have available a DHE 4RV 4 receiver voter system. Please note that 
this is an
older generation than the 4RV/2 which is currently being produced. This system
consists of a 4RV voter, a VCM, and power supply in a 19 inch rack 
mount. It was
removed from a site that was decommissioned and was not hooked up, so I do not
know the operational status. If interested, please e-mail me direct, 
off list. I would
prefer a trade, but all offers considered. Thanks and 73,

Kevin, K9HX

Re: [Repeater-Builder] fan timer circuit

[Bob M.]

I would think that the person who designed it, and submitted it for posting on 
r-b, built and tested it.

Did you have a problem with it? Do you think there's an error in the diagram? 
If so, it should be fixed. Please provide more info.

Bob M.
==
--- On Sat, 12/20/08, Michael Ryan  wrote:

From: Michael Ryan 
Subject: [Repeater-Builder] fan timer circuit
To: Repeater-Builder@yahoogroups.com
Date: Saturday, December 20, 2008, 1:57 PM

I was directed by someone on the reflector here some months back, to a cooling 
fan timer circuit that is posted on the repeater builders website. I wonder if 
anyone has tried to build this?
- Thanks
- Mike


  

[Repeater-Builder] fan timer circuit

[Michael Ryan]

 I was directed by someone on the reflector here some months back, to a
cooling fan timer circuit that is posted on the repeater builders website.
I wonder if anyone has tried to build this ?  - Thanks..  - Mike

[Repeater-Builder] Neat'o Swell - Projects and PC Board Web Page.

[skipp025]

Some neat projects and ideas available on this web page. 

http://www.w1ghz.org/small_proj/small_proj.htm 


enjoy, 
s. 

RE: [Repeater-Builder] RE: What Have I got and can I get information about it.

[Craig W Clark]

I have 3 of them,  One has HT-90 crystal controlled units inside. The other
2 are GP-300 and can be programmed. It is a bit of a hassle, as I do not
have whatever is the proper interface, so I took the units out and popped
them into gp300 cases and programmed them, then put them back into the
Systel. Works! If yours has very rectangled shaped units that are just
boxes, then it is most likely HT-90 and crystal controlled. Maybe you can
find crystals, not sure. But if the 2 units look like a HT out of the case
with speaker hole, kind of rounded corners, then it is probably the GP300
unit and much better. Mine work great with GMRS.

 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Rick Beatty
Sent: Thursday, December 18, 2008 12:37 AM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] RE: What Have I got and can I get information
about it.

 

I recently was given a SYSTEL unit made by Motorola, on 464.../469... with
duplexer and looks to be a repeater, with low level output (2w or so). Would
be great for remote work on GMRS, does anyone on the group have
data/information on this little cutie?

Also I am looking for a schematic for an amplifier used with the portable. a
UHF with the number N1275a? 

thanks in advance -- 

Rick 

 

Re: [Repeater-Builder] RC96 manual

[Rick Beatty]

John -- et al -- I opened the zip without issue and everything is there as
far as I can tell -- send me an email and I will send the 160 pages to you
-- LOL!

Rick

On Thu, Dec 18, 2008 at 2:43 PM, Joe  wrote:

>   Kevin sent this link and it works.
>
> http://www.repeater-builder.com/acc/acc-rc-96-manual.zip
>
> 73, Joe, K1ike
>
> John Transue wrote:
> > Joe,
> >
> > I get the same message when trying to download the file. I have a hard
> > copy but no electronic copy. Let me know if you want me to copy it for
> > you.
> >
> > John Transue
> >
>
>  
>

[Repeater-Builder] Re: VXR 7000 with desense

[pontotochs]

Hi Eric,
  Thanks, I haven't taken the cover off yet, but I will. And yes the
typo demon got me on the duplexer it is a DB 4062, 6 cavity duplexer.

  Regards,
Rick

--- In Repeater-Builder@yahoogroups.com, "Eric Lemmon"  wrote:
>
> Rick,
> 
> You might check to see if the internal jumpers inside the VXR-7000
cabinet
> are single-shielded.  I had a VXR-5000 UHF repeater that had
single-shield
> jumpers with gray jackets and no markings, and had a small amount of
> desense.  Once I replaced all three jumpers with RG-400/U
double-shielded
> cable, there was no trace of desense.  Perhaps Vertex tried the same
> money-saving trick on the later model.  Check to make sure that all
shields
> and cover plates are installed, with no screws missing.
> 
> I wonder if your duplexer has been mis-identified.  A DB4026 is a UHF
> bandpass cavity filter, not a duplexer.  You probably meant DB4062,
which is
> a six-cavity VHF BpBr duplexer.
> 
> 73, Eric Lemmon WB6FLY
> 

[Repeater-Builder] NHRC-Squelch Board

[twoway_tech]

Anybody have any NHRC-squelch boards in service? I am looking at
getting either one of those or a RLC-MOT board from link
Communications. Is one better then the other? Do they do the same
thing? Anybody try to clone an NHRC board? (they look easy)  I am
wanting to install something on a Mitrek for that nice Micor type
squelch. Actually, I just want to get rid of that Chkccc! 


Thanks,

Jordan

[Repeater-Builder] Re: VXR 7000 with desense

[pontotochs]

HI Jim,
  Thanks for the response, I was using the port on the 4304 to inject
the signal from the service monitor. The cables in the duplexer are
1/4 super flex.

  Nope your are not preaching to the choir. This is my first time
trying to trouble shoot a repeater system. So I know that there are
some subtleties that come with experience. Besides sometimes its the
obvious things that trip us up.

  Regards,
Rick

--- In Repeater-Builder@yahoogroups.com, Jim Brown  wrote:
>
> I don't know what type of service monitor you are using, but I tend
to use an iso-tee to measure desense with the duplexer hooked to a
dummy load through the iso-tee.  It might be possible for the service
monitor to contribute to some signal reflection if it is used as the
power termination.
> 
> Make sure the cables to the duplexer are double shielded, like
RG-214, and inspect the connectors to make sure all the grounds are in
good shape.  Check the internal cables in the VXR-7000 for the same
potential problems.
> 
> I may be preaching to the choir and if so I apologize.
> 
> 73 - Jim  W5ZIT
> 

RE: [Repeater-Builder] RE: What Have I got and can I get information about it.

[Craig W Clark]

Huh? Since when is a GP300 not type accepted for GMRS? News to me, but I
have been wrong before. (once!)

 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Milt
Sent: Thursday, December 18, 2008 2:12 PM
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] RE: What Have I got and can I get
information about it.

 

Rick,

 

The Systel was a 2 watt repeater with a telephone interconnect designed for
small on-site systems.  I doubt that it would be type accepted for GMRS as
it was based on one or more series of portables (HT-90 and/or GP300).  Of
course the phone patch would not be usable on GMRS either.

 

MIlt

N3LTQ

 

 

- Original Message - 

From: Rick Beatty   

To: Repeater-Builder@ 
yahoogroups.com 

Sent: Thursday, December 18, 2008 12:37 AM

Subject: [Repeater-Builder] RE: What Have I got and can I get information
about it.

 

I recently was given a SYSTEL unit made by Motorola, on 464.../469... with
duplexer and looks to be a repeater, with low level output (2w or so). Would
be great for remote work on GMRS, does anyone on the group have
data/information on this little cutie?

Also I am looking for a schematic for an amplifier used with the portable. a
UHF with the number N1275a? 

thanks in advance -- 

Rick 



 

[Repeater-Builder] Re: MSF 5000 vhf power amp TLD2692A manual query

[ghbyrkit]

Dear Bob,

I've got the MSR-2000 manuals for the repeater gear that I have to 
maintain.  I'd love to have the relevant manual sections for this 
power amp.  It's OK that the unit has sealed modules in it.  I'm 
looking for the specs, tuning info, schematic and all, so that I can 
maintain this unit when we deploy it in one of our club's 2m 
repeaters.

I'll gladly pay the price and accept the delay for getting the 
manual copied at the copy center!  Thanks so much for offering that 
possibility!  I bet that they could render it both as PDF and paper 
at the same time...

73,
George Byrkit, K9TRV
ARROW Technical coordinator (www.w8pgw.org)

--- In Repeater-Builder@yahoogroups.com, "Bob M."  
wrote:
>
> I've got a manual that has that PA in it. Not much there except a 
power splitter, two FET PA modules (undocumented), a power combiner, 
and a power sensor. There's some troubleshooting charts and some 
parts lists, but absolutely nothing on the actual PA modules 
themselves.
> 
> Most of the sheets are big fold-outs. Those with circuit board 
layouts are in color. It would take considerable time to scan them, 
plus it would be a very big file. Easier to make copies at the local 
copy center, but that wouldn't happen for several days and would 
cost several dollars plus postage.
> 
> I can give you specific info from the manual a lot faster.
> 
> Bob M.
> ==
> --- On Sun, 12/14/08, ghbyrkit  wrote:
> 
> > From: ghbyrkit 
> > Subject: [Repeater-Builder] MSF 5000 vhf power amp TLD2692A 
manual query
> > To: Repeater-Builder@yahoogroups.com
> > Date: Sunday, December 14, 2008, 11:54 AM
> > Hi, I've got an MSF 5000 VHF power amp, TLD2692A.  Does
> > anyone have a 
> > manual for this beast, or can you point me to a link for
> > one?  My 
> > meager attempts at google-fu didn't show anything that
> > I could 
> > identify as such, nor any on eBay, nor R-B website.
> > 
> > Thanks so much for reading, especially if you can help!
> > 
> > 73,
> > George K9TRV
> > (Technical Coordinator for ARROW, W8PGW.org)
>

[Repeater-Builder] Re: VXR 7000 with desense

[pontotochs]

Thanks to all who have responded. A quick up date.

Putting the dummy load on the TX port of the repeater (replace the
duplexer with a dummy load) has shown that the repeater works without
cycling - so my initial thought of something going on inside the
repeater is out the window... (Thanks Doug)

If is was spurious TX trash while the transmitter was coming up, then
after we overcame the desense with the service monitor and the TX
stabilized, then when we turned the service monitor back down, the TX
should have stayed on, but it didn't and started to cycle again

  Still racking the grey cells,
Rick, N5RB


--- In Repeater-Builder@yahoogroups.com, "pontotochs" 
wrote:
>
> Hi,
>   I've checked the previous posts on this issue, but I am hoping that
> there is more light to be shed.
>   We have a VXR 7000 that has had issues for a while as a two meter
> repeater.
> 
>   In the shop we set it up with its DB 4026 duplexer and 50 ohm dummy
> load and monitored the output power with a Bird thru line watt meter.
> We used a service monitor to inject the RX signal to get 10 dB
> quieting (approx 0.2 micro volt). Put the unit into repeat mode and
> the repeater will cycle (go in and out of transmit) until the RX
> signal is increased about 20 to 25 dB (approx 3.6 micro volt).
> 
>   Looking at what is coming in the receive port with the transmitter
> is keyed is about -75 dBw (50 watt out with about 95 dB of isolation)
> at the TX frequency, and there is little to no hash at the RX
> frequency - seeing the noise floor of the spectrum analyzer (-120 dB).
> 
>   Put the 7000 into base station mode, hooked up second signal source,
> set first signal source to give 10 dB quieting at the RX frequency
> (0.2 uV), set the second signal source to emulate what we saw from the
> duplexer (79 mV at TX frequency) and there was no desense. Increased
> the simulated TX voltage to better than 1 volt and still no desense.
> 
>   My thought is that something has gone bad internally within the
> 7000. Is there something else I need to try?
> 
>   Thanks in advance for your help.
> 
>   Regards,
> Rick, N5RB
>

[Repeater-Builder] Re: VXR 7000 with desense

[pontotochs]

Hi Doug,
  Thanks, I thought about the dummy load on the TX output directly on
the way home last night. So I am going to try it as soon as I can get
to it.
  I didn't think about checking the TX spectrum while the thing was
cycling - thanks.

  Regards,
Rick

--- In Repeater-Builder@yahoogroups.com, Doug Bade  wrote:
>
> Rick;
>  I think you need to isolate whether it is tx through the 
> duplexer or something else bothering the rx and or squelch. It sounds 
> like the tx signal fundamentally is clean from your analysis so far.. 
> in order to isolate through the duplexer, connect the tx directly to 
> a dummy load instead of it's side of the duplexer while injecting rx 
> into the duplexer. if it does not cycle, the tx is sending something 
> through the duplexer to the rxif it does cycle.. it is an 
> internal issue as you suspect.. I would use the tx to duplexer cable 
> in the dummy load path as you want to see if some radiation from it 
> is part of the equation.
> 
> I lean more to spurious on initial keyup... causing a noise burst 
> maybe due to exciter tuning... but this test should tell you if it is 
> conducted internally or passed through the duplexer.
> 
> Doug
> KD8B

Re: [Repeater-Builder] VXR 7000 with desense

[Rick Beatty]

Hi Rick -- I am new to the group so I have not seen all of the posts with
regards to your problem on the 7000. However, one thing that
you may want to check is whether the PL is feeding back into the RX from the
TX, if the tones are the same. I have seen this several
times in the past on different machines and it is always annoying.

Don't assume that just because you can run PL in and out that it will be
able to run the same tone.

GL -- Rick NU7Z

On Thu, Dec 18, 2008 at 9:44 AM, Doug Bade  wrote:

>   Rick;
> I think you need to isolate whether it is tx through the
> duplexer or something else bothering the rx and or squelch. It sounds
> like the tx signal fundamentally is clean from your analysis so far..
> in order to isolate through the duplexer, connect the tx directly to
> a dummy load instead of it's side of the duplexer while injecting rx
> into the duplexer. if it does not cycle, the tx is sending something
> through the duplexer to the rxif it does cycle.. it is an
> internal issue as you suspect.. I would use the tx to duplexer cable
> in the dummy load path as you want to see if some radiation from it
> is part of the equation.
>
> I lean more to spurious on initial keyup... causing a noise burst
> maybe due to exciter tuning... but this test should tell you if it is
> conducted internally or passed through the duplexer.
>
> Doug
> KD8B
>
> At 05:04 PM 12/17/2008, you wrote:
>
> >Hi,
> >I've checked the previous posts on this issue, but I am hoping that
> >there is more light to be shed.
> >We have a VXR 7000 that has had issues for a while as a two meter
> >repeater.
> >
> >In the shop we set it up with its DB 4026 duplexer and 50 ohm dummy
> >load and monitored the output power with a Bird thru line watt meter.
> >We used a service monitor to inject the RX signal to get 10 dB
> >quieting (approx 0.2 micro volt). Put the unit into repeat mode and
> >the repeater will cycle (go in and out of transmit) until the RX
> >signal is increased about 20 to 25 dB (approx 3.6 micro volt).
> >
> >Looking at what is coming in the receive port with the transmitter
> >is keyed is about -75 dBw (50 watt out with about 95 dB of isolation)
> >at the TX frequency, and there is little to no hash at the RX
> >frequency - seeing the noise floor of the spectrum analyzer (-120 dB).
> >
> >Put the 7000 into base station mode, hooked up second signal source,
> >set first signal source to give 10 dB quieting at the RX frequency
> >(0.2 uV), set the second signal source to emulate what we saw from the
> >duplexer (79 mV at TX frequency) and there was no desense. Increased
> >the simulated TX voltage to better than 1 volt and still no desense.
> >
> >My thought is that something has gone bad internally within the
> >7000. Is there something else I need to try?
> >
> >Thanks in advance for your help.
> >
> >Regards,
> >Rick, N5RB
> >
> >
>
>  
>

Re: [Repeater-Builder] DATARADIO 96+ Manual needed

[Rick Beatty]

Kenny, I sent you a copy of the manual -- unzipped --

Rick NU7Z

On Thu, Dec 18, 2008 at 2:56 PM, KG5KS - Kenny Thompson wrote:

>   Guess the ham that said he would send the manual has forgotten about
> it..hi  I need a manual with pinout or specs for the Dataradio 96+ unit.
> I'm wanting to see if they could be used in a ham radio application.  I have
> not found out anything online that would show me what pinouts and specs.  I
> appreciate it!
>
> Thank you
>
> 73
>
>
> Kenny
>
>
> ARS KG5KS
>
>
> Currently DEC B, EC Jackson County, OBS, ORS, ARRL VE
>
>
> Courses completed Nims 700, ICS 100, 200, 300, 400, 702, 317, 394, 240,
> 242, 139, 245, 275, 230, 235, 800, ARECC 1, Skywarn Certified Continuously,
> Past Public Safety Officer for State.
>
>  
>

[Repeater-Builder] Re: Want: GLB Receiver Pre-selector (please)

[skipp025]

Re: Want: GLB Receiver Pre-selector (please) 

Yes, the box and board Joe sent the picture in is one of 
the GLB Preamplifier beasts I'm looking for. 

I've seen this same and similar circuit appear in a number of 
receivers, pre-amplifiers, pre-selector circuits going way back 
to early EF-Johnson receivers. I would even guess they (EFJ Comp.) 
probably were not the inventors or first users of this almost 
exact "front-end" circuit layout. 

Spectrum (RIP) and a few other companies did offer the GLB and 
and similar variant units in some of their products.

Thank you to those who have already replied... no pre-amplifiers 
in hand yet, but I'm still looking and answering a few emails 
to fish a GLB out of the wood-work. Doesn't matter what band 
they are on, or condition (even in pieces). 

thanks much... 

cheers, 
skipp 

skipp025 at yahoo.com 


> Joe  wrote:
>
> It's definitely a GLB preselector, model P-147.49Mhz, Serial #7110.  
> That's what it says on the case.  This type of preselector was seen in 
> several pieces of equipment.  One that comes to mind was an option on 
> the SCR-77 Spectrum Repeater.  I have one in service right now, and I 
> suspect Spectrum might have gotten them from GLB. The attached photo 
> shows it sitting on top of the repeater. 
> 
> Scott Zimmerman wrote:
> > > Next, the brass tube helical resonators in your assembly look to me 
> > to be as made by ACS / Kendecom and as used in their repeater
receivers.
> >  
> > Yep they LOOK like them, but the're not. This is a typical looking
GLB 
> > preselector preamp.
> >  
> > Scott
> >  
> > Scott Zimmerman
> > Amateur Radio Call N3XCC
> > 474 Barnett Rd
> > Boswell, PA 15531
>

Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)

[Chuck Kelsey]

I've had to add wire to the helicals on two Micors (UHF) to get them down to 
447.75. It did the trick. It would certainly be worth a try.

Chuck
WB2EDV


- Original Message - 
From: "Eric Lemmon" 
To: 
Sent: Saturday, December 20, 2008 10:27 AM
Subject: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: 
Holiday Special...)


> Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081,
> 136-146 MHz) is still available from Motorola Parts.  That one is part
> 2480032A07, the violet coil in L1, for $ 4.15.
>
> The only option may be to tack on some extra wire to the existing coils.
> Although modifying the tuning screws may work, I suspect the Q will 
> suffer.
>
> 73, Eric Lemmon WB6FLY
>
> 

Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)

[Jim Brown]

This probably will not work on the Mitrek since it may not use slugs to tune 
the coil, but I had a problem with a crystal on a Delta radio that would not go 
low enough in frequency.  I removed the slug from the F2 coil and ran the slug 
for the F1 coil through max inductance and then added the second slug on top of 
the first.  The combined slugs allowed me to net the crystal.

73 - Jim  W5ZIT

--- On Sat, 12/20/08, Eric Lemmon  wrote:
From: Eric Lemmon 
Subject: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS:  
Holiday Special...)
To: Repeater-Builder@yahoogroups.com
Date: Saturday, December 20, 2008, 9:27 AM











Only one of the five front-end coils for a Range 1 VHF Mitrek 
(HLD4081,

136-146 MHz) is still available from Motorola Parts.  That one is part

2480032A07, the violet coil in L1, for $ 4.15.



The only option may be to tack on some extra wire to the existing coils.

Although modifying the tuning screws may work, I suspect the Q will suffer.



73, Eric Lemmon WB6FLY

 



-Original Message-

From: Repeater-Builder@ yahoogroups. com

[mailto:Repeater-Builder@ yahoogroups. com] On Behalf Of Kevin Custer

Sent: Friday, December 19, 2008 9:30 PM

To: Repeater-Builder@ yahoogroups. com

Subject: Re: [Repeater-Builder] Holiday Special - MICOR 2 meter receiver

conversion from W3KKC



Tom,



Okay   I guess I should ask if replacement coils for the Mitrek are

still available from Motorola, and if so, at what cost?  If they are no

longer available, or are cost prohibitive, send me one of your Mitrek

receivers and I'll see if I can come up with a new set of coils that

properly tune the whole 2M band.

I guess at this point we should go to private email.



Kevin



Hello Kevin

Thanks for your reply.  Your statement is correct in that all of

the receiver coils begin to tune at the bottom of their travel.  I have even

tuned two or three too far and they dropped out with the resulting work to

retrieve the screws.  When tuned as best I can for sens the s/n ratio is

1+uv at 12db sinad.  The original frequency sens was less than 1uv-usually

about .3uv for 12db sinad.  Replacing the coils are about the only solution

I know of for these high split VHF units.  I have in the past replaced two

sets of receiver coils with Motorola coils and found I have good sensitivity

as before modification.  The transmitters all tuned well on this split and

gave rated or more power output. 

The Mitrek coils looked very much like the Micor coils.  I have

replaced probably a half dozen Micor receiver coils proscured from Motorola

in the past 20 or so years. Thanks. 73 de Tom Manning, AF4UG



- Original Message - 

From: Kevin Custer   

To: Repeater-Builder@ yahoogroups. com

  

Sent: Thursday, December 18, 2008 10:02 PM

Subject: Re: [Repeater-Builder] Holiday Special - MICOR 2

meter receiver conversion from W3KKC



Tom,



You say you find similar operation on 4 or 5 units.  By that

do you mean they won't make book specification on any frequency below 146

MHz?  If that is the case, I would believe something is wrong.  I have seen

many Mitrek high-band receivers that were tuned for 144 something and had

very good sensitivity.



Let me ask you this   When tuned at 144.89, is the

front-end tuning all "one ended", or is there adjustment to spare?  In other

words, can you tune the front-end without the fear of the tuning screws

falling into the casting?  If you have room left to go lower in frequency,

then the front-end is not the problem, and you'll need to look elsewhere for

the lack of sensitivity.   Another question -  do these 4 or 5 units tune

and make book spec sensitivity on their original high-band channel?



I guess what I'm saying is I doubt the problem is the

front-end helical resonators, but if there is a need for a conversion I'm

not opposed to looking into making a modification available, if it is

needed.  If there are others on the list that have had good luck with the

Mitrek on frequencies below 146 MHz, please chime in and let us know what

you have and how well it works.  



Kevin









Hello Kevin

You are correct on your freqs for xmit and rcv.

The Mitrek units I  have will only tune receive to 146.00Mhz.  This leaves

more than one meg to go to meet tolerance on 144.890.  I have tried 4 or 5

units and find similar operation of all.  This is the reason for my question

about the Micor coils working for Mitrek.  Thanks.  73 de Tom Manning, AF4UG



- Or

[Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)

[Eric Lemmon]

Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081,
136-146 MHz) is still available from Motorola Parts.  That one is part
2480032A07, the violet coil in L1, for $ 4.15.

The only option may be to tack on some extra wire to the existing coils.
Although modifying the tuning screws may work, I suspect the Q will suffer.

73, Eric Lemmon WB6FLY
 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Kevin Custer
Sent: Friday, December 19, 2008 9:30 PM
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] Holiday Special - MICOR 2 meter receiver
conversion from W3KKC

Tom,

Okay   I guess I should ask if replacement coils for the Mitrek are
still available from Motorola, and if so, at what cost?  If they are no
longer available, or are cost prohibitive, send me one of your Mitrek
receivers and I'll see if I can come up with a new set of coils that
properly tune the whole 2M band.
I guess at this point we should go to private email.

Kevin




Hello Kevin
Thanks for your reply.  Your statement is correct in that all of
the receiver coils begin to tune at the bottom of their travel.  I have even
tuned two or three too far and they dropped out with the resulting work to
retrieve the screws.  When tuned as best I can for sens the s/n ratio is
1+uv at 12db sinad.  The original frequency sens was less than 1uv-usually
about .3uv for 12db sinad.  Replacing the coils are about the only solution
I know of for these high split VHF units.  I have in the past replaced two
sets of receiver coils with Motorola coils and found I have good sensitivity
as before modification.  The transmitters all tuned well on this split and
gave rated or more power output. 
The Mitrek coils looked very much like the Micor coils.  I have
replaced probably a half dozen Micor receiver coils proscured from Motorola
in the past 20 or so years. Thanks. 73 de Tom Manning, AF4UG

- Original Message - 
From: Kevin Custer   
To: Repeater-Builder@yahoogroups.com
  
Sent: Thursday, December 18, 2008 10:02 PM
Subject: Re: [Repeater-Builder] Holiday Special - MICOR 2
meter receiver conversion from W3KKC


Tom,

You say you find similar operation on 4 or 5 units.  By that
do you mean they won't make book specification on any frequency below 146
MHz?  If that is the case, I would believe something is wrong.  I have seen
many Mitrek high-band receivers that were tuned for 144 something and had
very good sensitivity.

Let me ask you this   When tuned at 144.89, is the
front-end tuning all "one ended", or is there adjustment to spare?  In other
words, can you tune the front-end without the fear of the tuning screws
falling into the casting?  If you have room left to go lower in frequency,
then the front-end is not the problem, and you'll need to look elsewhere for
the lack of sensitivity.   Another question -  do these 4 or 5 units tune
and make book spec sensitivity on their original high-band channel?

I guess what I'm saying is I doubt the problem is the
front-end helical resonators, but if there is a need for a conversion I'm
not opposed to looking into making a modification available, if it is
needed.  If there are others on the list that have had good luck with the
Mitrek on frequencies below 146 MHz, please chime in and let us know what
you have and how well it works.  

Kevin




Hello Kevin
You are correct on your freqs for xmit and rcv.
The Mitrek units I  have will only tune receive to 146.00Mhz.  This leaves
more than one meg to go to meet tolerance on 144.890.  I have tried 4 or 5
units and find similar operation of all.  This is the reason for my question
about the Micor coils working for Mitrek.  Thanks.  73 de Tom Manning, AF4UG

- Original Message - 
From: Kevin Custer
  
To: Repeater-Builder@yahoogroups.com
  
Sent: Tuesday, December 16, 2008 8:44 PM
Subject: Re: [Repeater-Builder] Holiday
Special - MICOR 2 meter receiver conversion from W3KKC


Tom,

Do you mean 144.89 MHz?  I would think your
repeater would *transmit* on 145.490 MHz  At any rate, no conversion is
necessary for the Mitrek to make book specification sensitivity on 144.890
MHz.