开云体育

Hi Chris:

On Wed, 31 Mar 1999 16:37:41 -0800, csnichol wrote:

The document I have states the operating freq's are 52.87/53.87
Should be close enough to work anywhere in the 52/53 range.

You would think so, but why is the SWR so high going into a
dummy load? What I'll try is use your frequencies and see what
I get for loss and isolation. That way we'll know if it's the
cans or the harness that's out-of-spec.

I'm running 200 watts into the thing (50 w over the cont. power
rating) with no desense. I'm using a Motorola Micor 330w station.
What are you using for for RF gear?

WOW!! 200 Watts....I can dream, can't I :)

Using a stock GE Mastr II mobile turned down to between 30
and 50 watts.


Tedd Doda CET CEO

Lazer Audio and Electronics

packet ve3tjd@va3sed
e-mail lazer@...

Hi Guys: I got an answer from Db probucts concerning the
4032 duplexor. not what I wanted, but......

On Wed, 31 Mar 1999 08:11:01 -0600, Davis, Coy wrote:

RE; YOUR REQUEST FOR INFO. CABLING OF DB4032 DUP. 52.37 AND
53.37 Mhz.


Reduce all cables by 1 full ". This includes any and all
shorted stubs. .this will get you in the
Range of acceptable performance. We have not offered this product
above 50.0 mhz. Consequently the
Exact cabling has not been developed. There is no formula that will
give you the exact lengths required.
I hope this bit of information will be somewhat helpful, good luck
with this project.

Regards;
Coy Davis
Specials Coordinator

Tedd Doda CET CEO

Lazer Audio and Electronics

packet ve3tjd@va3sed
e-mail lazer@...

Hi Chris:

On Tue, 30 Mar 1999 16:32:32 -0800, csnichol wrote:

Tedd, here is the info I got from DB and it worked for mr

I used the the old open stubs to make the new shorted stubs.
I made new open stubs.
I did NOT change any other cables as they were close enough.
You must trim the helix
This data is for a 1MHZ split
This data came from a document numbered MKT019/A 3-20-95,
not an official engineering document but something from
DB's marketing dept. with disclaimers attached
It worked for me.

I tried it the first time you sent it to me and it didn't
make much difference, but I tried it again yesterday, making
all new cables, and it help alot. I think the first time I
included the connector length, but noticed the second time
that the length was "cut" length!

The SWR going into the TX port is now a respectable 1.7 to 1,
from a 3 to 1 (still a little high), but the SWR going into
the RX port went from 2.9 to 1 down to 1.2 to one. This is
using an MFJ 259 with a cellwave 50 ohm dummy load (ex cellular
circulator stuff).

When you got the dimensions from Db, did you specify a TX
and RX pair? I'm hoping that something is just slightly off
as the desense is still very obvious with only a 30 watt
drive (into a dummy load, doesn't make much difference going
into a home-brew "J" pole so the antenna must be ok).

I called Db products in Texas (yes, the 800 number works North
of the boarder!), but could only leave voice-mail for the Techs.


Tedd Doda CET CEO

Lazer Audio and Electronics

packet ve3tjd@va3sed
e-mail lazer@...

Tedd, here is the info I got from DB and it worked for mr

open the cans and trim the helix to 7 1/4 turns.
pop rivet the cans back together.
cable lengths are cut lengths and do not include connector
on the low freq side...
can to tee length 14 3/4 " QTY 3
SHORTED stub length 19 1/2 QTY 3
interconnecting cable 29 1/2 QTY 2
on the high freq. side...
can to tee length 29 1/2 QTY 3
OPEN stub 21 1/2 QTY 3
interconnecting cable 41 3/4 QTY 2
for the Y cable at the antenna 41 3/4 qty 2


I used the the old open stubs to make the new shorted stubs.
I made new open stubs.
I did NOT change any other cables as they were close enough.
You must trim the helix
This data is for a 1MHZ split
This data came from a document numbered MKT019/A 3-20-95,
not an official engineering document but something from
DB's marketing dept. with disclaimers attached
It worked for me.

Chris
N9LLO
53.39 Kokoko In.

Tedd Doda wrote:

Hello again Tom..
I have some limited experiance tunning duplexers on two meters ( Wacom
).... It may help to draw yourself a picture of what you want your
duplexer to do. For example on mine for two meters, I want my high side
( transmit ) to pass 146.91 with the notch set at 146.31 ( recieve )...
On my low side I want to pass 146.31 with that notch set on 146.91...
For Me it has been easyiest to rough them in if necessary by
transmitting into ( 5 watts or less ) each pair of duplexers with a 50
ohm or 100 ohm at the output of that pair, also connect a wattmeter to
that output..
On the transmit pair, tune the pass for max at your transmit freq..
Then with same hookup, switch the 5 watts to the recieve freq. and set
your notches for minimum...
Do just the opposite with the recieve pair of cans...
You may need to touch them up after reconnecting everything...
One last thing is that the swr into the transmitt port may not be 1 to
1..... It has been sugested to me that I tweak the lenth of cable from
transmitter to duplexer for max power to the antenna...

73 Elmer KB3WG

From: "Tedd Doda" <lazer@...>
Reply-To: Repeater-builder@...
To: "Repeater list" <repeater-builder@...>
Subject: [Repeater-builder] Help with dB 4032
Date: Tue, 30 Mar 1999 09:43:16 -0500

From: "Tedd Doda" <lazer@...>

Hi Guys:

Can anyone point me in the right direction.....I started
tuning up my db-4032 6 meter duplexor and after setting
the cans, the SWR on the TX port is over 3-to-1. When I
got the set, it was set for TX on the low port and RX
on the high port. I have it set for the standard 6 split
of TX on 53.37, and RX on 52.37 (standard for Ontario).

Do I have to swap the open/close stubs to get this thing
to work properly?


Tedd Doda CET CEO

Lazer Audio and Electronics

packet ve3tjd@va3sed
e-mail lazer@...



------------------------------------------------------------------------
Ideas on how we can improve ONElist?

Check out the Suggestion Box feature on our new web site
------------------------------------------------------------------------
This list is sponsored by the owners and users of "RBTIP"

Get Your Private, Free Email at

Oh Tom I just wanted to say, on the Master II audio, that I don't think
either side of the audio output is grounded....

73 again Elmer KB3WG

From: "Tedd Doda" <lazer@...>
Reply-To: Repeater-builder@...
To: "Repeater-builder@..." <Repeater-builder@...>
Subject: [Repeater-builder] Re: Mastr II CAS to PTT (simple)
Date: Tue, 30 Mar 1999 09:30:59 -0500

From: "Tedd Doda" <lazer@...>

On Mon, 29 Mar 1999 20:04:22 PST, ELMER HOKEY wrote:

I have been using a master II on 2 meters for a long time with a
controller. It should not be difficult to get your recieve audio to

the

transmitter, but it will sound tinny if you take audio from the volume
control( before deemphisis ). the easyiest way is to use the speaker
output...

That's what I'm using now. Took the spk/hi terminal, through
a 2.2uF cap into a 10k pot, feeding the mic/hi terminal. I
find the TX audio "rough"? I thought it would be a smoother
response, but I guess it's easier than taking the descriminator
audio, amplifying it, then using the PL input, hi!


Tedd Doda CET CEO

Lazer Audio and Electronics

packet ve3tjd@va3sed
e-mail lazer@...



------------------------------------------------------------------------
If you like orange and blue, then you will love our new web site!

Onelist: Fostering connections and information exchange
------------------------------------------------------------------------
This list is sponsored by the owners and users of "RBTIP"

Get Your Private, Free Email at

Hi again guys:

Here is a partial view of the 4032 duplexer. maybe someone
can explain to me how these things work, then I could scale
it up to 53 Mhz???? (Please use a non-proportional font)


(can) (can)
xxx Shorted stub Open stub xxx
xxxxx ^ ^ xxxxx
xxx ^ ^ xxx
| ^ (2) (3)^ |
| ^ ^ |
|(1) ^ ^ (4)|
Lo _____|______________|_____(5)__________________|_____________|_____ Hi
Freq | Freq
(RX) | (TX)
|
ANT

The dimensions are as follows:

1 = 14 3/4"
2 = 15"
3 = 27"
4 = 29 1/2"
5 = 29 1/2"

Ed mentioned that-- One strange thing, is that a notch cavity at
the end of a 1/4 line becomes a "band pass"???

This really throws me for a loop!

Can I just scale these cables by say 15 %?

Tedd, VE3TJD

Hi Ed:

On Tue, 30 Mar 1999 10:22:00 -0500, Ed Bathgate, RMA Repair Dept x8785 wrote:

I saw a picture of similar unit, is this duplexer factory
tuned for 6m? If not, you may need to trim or adjust all
the cable lengths and stub lengths.

It was tuned for 45 Mhz TX and 46 Mhz RX. I thought I would
have to modify the cables, but without a formula for calculating
the lengths, could become a real hassle.

I rebuilt a sinclair hybrid ring duplexer, 2m, and it used
open 1/4 stubs that were adjustable on the end for a
notch frequency. If your tx stub is trying to notch
your tx freq, your swr will be hi and your insertion loss
will be tremendous. The TX side stub should notch out your
rx freq, and vise versa on rx side.

On this unit, they have 3 notch cans for RX and 3 for TX. The
diagram I have for it label the 2 ports "high port" and "low
port" which is what is expected. Being that they were tuned
for almost 8 megs down from 53, the stubs would be out to left
field.

Disconnect your rx, and try removing the stub and check swr
again, if its better, you will need to play with the cable
lengths. We put hi tx energy into our rx, and roasted 2
mosfets!

I'm afraid of doing the same thing, hi! I e-mailed dbProducts
and hope that they can help.

I rough tuned the stubs with a T connector and a swr meter
and dummy load. When the stub was "on freq" the swr went
hi. I used an HT on low power that could handle hi swr
and not croak.

The "cans" are working well individually. I can tune all
six to reject the proper frequency. I tried to reverse-
engineer the stub lengths, but this was a lesson in futility :)
There were 4 lengths within the duplexor that worked out
to be a 1/4 wave length in dimension, taking in effect the
velocity factor (at 45 Mhz). The hassle with these things
is that there are 13 "T" fittings, and trying to measure
the lengths including these is difficult!

Thanks for the help Ed, give me some things to try...

Tedd, VE3TJD

Can anyone point me in the right direction.....I started
tuning up my db-4032 6 meter duplexer and after setting
the cans, the SWR on the TX port is over 3-to-1. When I
got the set, it was set for TX on the low port and RX
on the high port. I have it set for the standard 6 split
of TX on 53.37, and RX on 52.37 (standard for Ontario).

Do I have to swap the open/close stubs to get this thing
to work properly?

I saw a picture of similar unit, is this duplexer factory
tuned for 6m? If not, you may need to trim or adjust all
the cable lengths and stub lengths.

I rebuilt a sinclair hybrid ring duplexer, 2m, and it used
open 1/4 stubs that were adjustable on the end for a
notch frequency. If your tx stub is trying to notch
your tx freq, your swr will be hi and your insertion loss
will be tremendous. The TX side stub should notch out your
rx freq, and vise versa on rx side.

Disconnect your rx, and try removing the stub and check swr
again, if its better, you will need to play with the cable
lengths. We put hi tx energy into our rx, and roasted 2
mosfets!

I rough tuned the stubs with a T connector and a swr meter
and dummy load. When the stub was "on freq" the swr went
hi. I used an HT on low power that could handle hi swr
and not croak.

My $.02

Ed N3SDO


Ed Bathgate RMA Dept (724) 772-8785
pager (412) 649-6773

I have been looking for any replies to this message because I had a few
questions also. Where is the best place to obtain a voltage for cas high or low?

Bill WA9BA

HQ54@... wrote:

Hi Guys:

Can anyone point me in the right direction.....I started
tuning up my db-4032 6 meter duplexor and after setting
the cans, the SWR on the TX port is over 3-to-1. When I
got the set, it was set for TX on the low port and RX
on the high port. I have it set for the standard 6 split
of TX on 53.37, and RX on 52.37 (standard for Ontario).

Do I have to swap the open/close stubs to get this thing
to work properly?


Tedd Doda CET CEO

Lazer Audio and Electronics

packet ve3tjd@va3sed
e-mail lazer@...

On Mon, 29 Mar 1999 20:04:22 PST, ELMER HOKEY wrote:

I have been using a master II on 2 meters for a long time with a
controller. It should not be difficult to get your recieve audio to the
transmitter, but it will sound tinny if you take audio from the volume
control( before deemphisis ). the easyiest way is to use the speaker
output...

That's what I'm using now. Took the spk/hi terminal, through
a 2.2uF cap into a 10k pot, feeding the mic/hi terminal. I
find the TX audio "rough"? I thought it would be a smoother
response, but I guess it's easier than taking the descriminator
audio, amplifying it, then using the PL input, hi!


Tedd Doda CET CEO

Lazer Audio and Electronics

packet ve3tjd@va3sed
e-mail lazer@...

On Mon, 29 Mar 1999 16:55:36 -0500, tom oliver wrote:

Transmit audio can come from the last pin onthe ifas board (I think) labled
rx pa on the schematic you can run this into the mic hi input but do it
through a sutable capacitor to keep the dc off It sounds decent but your
volume switch becomes your repeat audio control.

Thanks Tom. I'll try that next time I open the radio!


Tedd Doda CET CEO

Lazer Audio and Electronics

packet ve3tjd@va3sed
e-mail lazer@...

Hello Tedd
I have been using a master II on 2 meters for a long time with a
controller. It should not be difficult to get your recieve audio to the
transmitter, but it will sound tinny if you take audio from the volume
control( before deemphisis ). the easyiest way is to use the speaker
output... 73 Elmer KB3WG

From: "Tedd Doda" <lazer@...>
Reply-To: Repeater-builder@...
To: "Repeater list" <repeater-builder@...>
Subject: [Repeater-builder] Mastr II CAS to PTT (simple)
Date: Mon, 29 Mar 1999 12:57:12 -0500

From: "Tedd Doda" <lazer@...>

Hi Guys:

I was playing with my Mastr II on 6 meters, getting ready to
devise a way to get PTT from the CAS line (no controller yet).

I tried a 2n3904, but found that it loaded the CAS line. I then
remembered, from repairing TNC's, that they use a 2n7000 FET.
Knowing that the FET has a very lite loading, I tried it. It
works very well, and absolutely no false triggering.

Hoping that this may help someone, here is the scoop:

The 2n7000 has the pin-outs (with the transistor facing you):

1 2 3

Source Gate Drain

-Take the SOURCE to a good ground
-Take the GATE directly to the CAS line
-Take the DRAIN directly to the PTT line

That's it! Works well, and the CAS line doesn't drop at
all in voltage. Just remember to follow standard "anti-
static" precautions.

Now, if I could find a simple solution for the TX audio, hi!


Tedd Doda CET CEO

Lazer Audio and Electronics

packet ve3tjd@va3sed
e-mail lazer@...



------------------------------------------------------------------------
Come check out our brand new web site!

Onelist: Making the Internet intimate
------------------------------------------------------------------------
This list is sponsored by the owners and users of "RBTIP"

Get Your Private, Free Email at

Lloyd wrote:

Hi the name is Lloyd, the call is VE7-LWB. I have a small radio shop and
I can tune cavity cans for anyone that wishs. This is not a screw driver type
outfit, but I do it the right way, with the right equipment, a network analyzer
from HP. I work with frequencies from HF right up to 2 GHz and some
of the equipment I have goes up to 18 and 24 gigs. I make this offer to hams
that need cavities tuned, as I know that it can be very pricey at times.
I am located in the Vancouver area.

---------------------------------------------------------------
Hi the name is Lloyd, the call is VE7-LWB. I have a small radio shop
and
I can tune cavity cans for anyone that wishs. This is not a screw
driver type
outfit, but I do it the right way, with the right equipment, a network
analyzer
from HP. I work with frequencies from HF right up to 2 GHz and some
of the equipment I have goes up to 18 and 24 gigs. I make this offer
to hams
that need cavities tuned, as I know that it can be very pricey at
times.
I am located in the Vancouver area.

HI Lloyd:

This may be off topic, but I will give it a try...Someone told me during
my last trip to Seattle, Wa. last year that either B.C. or Vancou., CA
make good Complete Set of Transmitter for FM Broadcast Station (Stereo),

Can you please help me and perhaps look at your yellow pages for sources
where I can procure this kind of equipment.

I am planning in setting up a small FM Broadcast Station in a small
village -3ooo population... and powered by about 1 or 3 watts in and
boost to abut 25 or 75 watts out. I intend to stay away from 100 watts.

Help,

Chris S. Inos
wh6um

As promised I have the information on the FM broadcast transmitter and
amp I have and have used to cover a complete town.

The unit I have is called a Wavemach FMS-2 exciter
I also have a 2.5 watt amplifier that matches the exciter.

Here are some pix of the exciter and amp.

[Wavemach FMS2 Broadcast Exciter]

[Wavemach 2.5 watt add on amplifier]

For a complete listing of this equipment, Go to


--
Please disregard my sending address of
kuggie@... I am using an alternate
ISP for sending messages only. (shol.com)

Kevin Custer W3KKC
kuggie@...

--
Please disregard my sending address of
kuggie@... I am using an alternate
ISP for sending messages only. (shol.com)

Kevin Custer W3KKC
kuggie@...

"Kevin K. Custer W3KKC" wrote:

Transmit audio can come from the last pin onthe ifas board (I think) labled
rx pa on the schematic you can run this into the mic hi input but do it
through a sutable capacitor to keep the dc off It sounds decent but your
volume switch becomes your repeat audio control.

good luck

tom n8ies

Tedd Doda wrote:

Hi Guys:

I was playing with my Mastr II on 6 meters, getting ready to
devise a way to get PTT from the CAS line (no controller yet).

I tried a 2n3904, but found that it loaded the CAS line. I then
remembered, from repairing TNC's, that they use a 2n7000 FET.
Knowing that the FET has a very lite loading, I tried it. It
works very well, and absolutely no false triggering.

Hoping that this may help someone, here is the scoop:

The 2n7000 has the pin-outs (with the transistor facing you):

1 2 3

Source Gate Drain

-Take the SOURCE to a good ground
-Take the GATE directly to the CAS line
-Take the DRAIN directly to the PTT line

That's it! Works well, and the CAS line doesn't drop at
all in voltage. Just remember to follow standard "anti-
static" precautions.

Now, if I could find a simple solution for the TX audio, hi!


Tedd Doda CET CEO

Lazer Audio and Electronics

packet ve3tjd@va3sed
e-mail lazer@...