Bill,
Looks like those cavities will bolt together end to end.
All four would make a nice single 6m cavity.
The 3 1/8 elbows look to be good quality and are always in demand for high
power FM radio work. Keep these and their inner bullets.
The 3dB couplers look to be machined from a single
Just a thought,
Why dont you turn the pistons around to give you a longer reach?
Ian
G8PWE
- Original Message -
From: Burt Lang b...@gorum.ca
To: Repeater-Builder@yahoogroups.com
Sent: Saturday, July 17, 2010 4:08 PM
Subject: Re: [Repeater-Builder] Re: Invar Rods
What diameter are
Kris,
These filters are constant impedance designs so the transmitters unwanted
sideband power gets dumped into a load on the Hybrid port. This also helps
with group delay at edges of the filtered response.
... cant see why a ham would make a filter with twice as many cavities than
needed, just
Wullie,
Having moved many of these particular devices from 142 mhz to 145 mhz
I would follow this proceedure.
Check it on its original frequencies for insertion loss and isolation.
The Pass band on 1db per division should be around 20 mhz.
The isolation plot will be much more narrowband ..around
Guys,
An update on the beer barrel 2m duplexer project.
(please read the embedded .pdf file for background information)
http://www.radiohamzone.com/Beer_Barrel_MK3/Beer_Barrel_MK3.htm
Ian
G8PWE
Guys,
Update on the 70cm duplexer project using surplus Tetra/Dolphin motorised
cavities.
http://www.radiohamzone.com/DolphinDuplexers/dolphin_duplexers_build.htm
Ian
G8PWE
Ron,
A couple of UK repeaters are dual standard d-star / Analogue.
Digital/auto/analogue switching is achieved via an embedded suffix in the
d-star path description.
Its a good way to introduce people to d-star. Analogue users need CTCSS enabled
to mute the d-star noise
See
Paint a polythene cup with your favourite antenna covering. Let it dry and put
it into the microwave oven along with a cup of water (to act as a dummy load)
Cook for 1 min on max power.
If it gets even slightly warm its no good for antennas.
er.. can I please have an award for the first cooking
Eric,
Thanks for doing that research
I see a cable spec MIL-C-17/75G in my latest suppliers catalogue. Is this the
new cable to which you refer?
Also have you seen any information on connectors for this new cable.
Specifically, do you remove the foil before crimping the braid ?
Ian
G8PWE
-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of IM Ashford
Sent: Saturday, April 12, 2008 11:19 AM
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] New RG-214 Cable has an aluminum tape layer
Eric,
Thanks for doing that research
I see a cable spec MIL
Dave,
You didn't have to upset all the nice people on here... I also have the
software..(a paid for copy)
Is your machine an exported MSF5000 ie MSF1 ?
If so, There is some nice software to turn the machine into a repeater
referred to at:
www.vfdb.net/vus/dss2/umbau_DSS_DL1XM.pdf
Paul,
Excellent photos!
The only reason these two pieces of metal have began touching each other is
that the invar plunger or the silver tuning sleeve have become bent.
This could be due to some rough handling of the unitsprobably when you were
absent?
Personally, I would drill a series
OK,
There was a long and detailed thread about z matchers on this group abou a year
ago?
Lots of interesting stuff about line matching emerged.. dont take my word for
it have a look in the archives...
I can only describe what I measure and that is cable leakage from a jumper
between the
OK so you have a reel of cable and two connectors to make up the jumper between
transmitter and duplexer.
The duplexer is tuned using 50 ohm test gear and the transmitter has been
optimised into a 50 ohm load.
Unfortunatley the output impedance of the transmitter is not 50 ohms and a
length
Look on he positive side.
We switched our analogue phone network off 10 years ago and as hams we are
still collecting and reusing all that stuff.. like hundreds of feet of rg400
with connectors,erricson and Motorola combiners that can be modified as 440mhz
duplexers(they are 3/4 wave at
Dingotel are a VOIP telephony provider, all traffic goes over their network.
This is most unsatisfactory for a 2 way radio system that needs privacy and low
latency.
The dingotel product is USB driven, who wants a PC on a mountaintop?
Im sure this thread has been discussed before...
G8PWE
Uk
How about the Sipura sp1000 series?
Set one to broadcast and the other to hotline, turn all ringing and line tones
off.
The codec type is selectable or automatic and you can use your own 2 to 4 wire
converter.
Also available in your price range...
Ian
G8PWE
- Original Message -
Quasi .. that just means virtual.
Some manufacturers, in the interests of meaningless product diferentiation,
choose words for effect.
Looking at the article it seems that the quasi part is a precision offset to
each base stations frequency so that a stationary mobile will not stay in a
null.
OK Sylvain,
I tried the spreadsheet in Excel 2000 all ok.
Excel 2003 - no frequencies calculated.
The results are in .hex format.
If you give me your frequency I will make a .BIN file for you.
G8PWE
Birmingham UK
- Original Message -
From: Sylvain VALAT (F1UJT)
To:
Marconi RC690 is a 25w AM radio.
Perhaps thats why your rx audio is so bad,its slope detecting the FM.
You could use the radios just talking to each other on an AM only net...
Ian G8PWE
UK
- Original Message -
From: vince
To: Repeater-Builder@yahoogroups.com
Sent: Thursday,
This sounds perfect for a backup control system.
However, using mobile phone/gsm to control primary systems
has the following problems.
1) Latency - texts can sometimes be late.I have known a delay of 24 hours
during Christmas and new year peaks.
2) Spam texts - the phones inbox fill with offers
Dave,
Having looked at the GB3FH website,this duplexer looks to be self compensating.
Any expansion due to heating of the heliax inner should be compensated by
expansion of the linking feeder inner,pushing the tuning bar upwards.
I have doubts as to the small effect on tuning that 0.2mm
Thank you Bob,Trev,Nate,Gary and VA7AA.
All of your comments have been most helpful
To summarise:
Decouple the antenna from the tower
Improve feeder bonding
Use conductive grease on sliding sections.
Ian
G8PWE
Central England
www.gb3dx.net
Yahoo! Groups Links
* To visit your group
anyway, but they are
not easy first steps to help find the actual problem.
cheers,
skipp
IM Ashford [EMAIL PROTECTED] wrote:
All of your comments have been most helpful
To summarise:
Decouple the antenna from the tower
Improve feeder bonding
Use conductive grease
Has anyone experience with eliminating noise fom the metalwork of a wind up
tower?
Our tower has 4 sections and is of the type where all sections raise at once
with a single cable pulley system.
The Machine is a Nokia BRS150 using a Sinclair Duplexer on 145.7625/1625
Antenna is Jaybeam Folded
Anybody using the MFJ 1516 repeater antenna ?
http://www.mfjenterprises.com/products.php?prodid=MFJ-1516
How long do they last on a non-hilltop environment ?
Would you use one on a commercial tower?
Any comments gratefully recieved - good or bad
Ian
G8PWE
www.gb3dx.com
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