How To Tune A Duplexer
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- čas přidán 26. 11. 2015
- In this how to video, a Sinclair Technologies engineer demonstrates step by step how to properly tune a duplexer filter. Mike the engineer also gives suggestions on preventing damage to the unit and the network analyzer while tuning.
For more information on our RF products or calibration services, please go to www.sinctech.com/installation-... or call 1-800-263-3275.
DISCLAIMER:
Our warranty does not cover improper tuning by the customer.
WARNING:
These types of devices should not be tuned under transmitter power levels because this can potentially damage the device, any equipment attached to it and poses a danger to the operator.
We have an RF engineer in our club that was able to do this for us,but its' neat to see how it's done.. We've had the same Sinclair 2 meter duplexer since the 1990's , it needed a bit of touchup a couple of years ago ,considering it's been in a block building for 30 + years , it's certainly understandable .. We also used to have a Sinclair 8 bay folded dipole array,which was amazing ....
Thanks for showing this ..
I love getting to tune the Sinclair duplexers. I am not in anyway a part of Sinclair so please keep that in mind. Just wanted to say that Sinclair makes a great duplexer!! I have never had a problem in getting it setup perfect!!!!!!!
Thank you Chris for the kind words! We glad you like our duplexers!
Thank you. This helped me greatly in understanding the Anritsu SiteMaster and what it was giving me for readings. I had peaked the frequencies not notched.
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Thanks, this video was very informative!
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Great video.
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Good job
Nice video other than the music at the beginning and end being 10x louder than the rest.
Sinclair products are excellent. Duplexers are simple to tune. I do not have ant fancy test gear. I use a generator and a receiver to tune at first , then touch up with low power to the inputs hi/low with a watt meter and set to minimum reflected. Have had duplexers checked with an instrument and spot on.. Wish I could own an instrument ...but $$$ which vI do not have. Have also built multicouple sets the same way.. Using a Motorola XPR radio with the RSSI reading as my guide. Can set insertion loss and a wattmeter for reflected .. The loop position is very important !! .... they work..
EXELENTE
No mention was made as to the position of the loop to control IL and or reject depth. Also the importance of the proper frequency dependent length of the cabling harness. Good video nevertheless.
where do you get those soldered T pieces...!!
I do not have a VNA so I'm trying to use the SA-TG for this. I understand the lower display of the R&S VNA to be the S21 return loss. I don't quite get how to duplicate the SWR reading of the upper two screens though. I can get a directional coupler but would that require an additional 50ohm load at the T connector when trying to measure the SWR? This would be the directional coupler to the T and instead of a wire back to the VNA as in the video, I terminate it with a 50ohm load. Is that about right?
Nice
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GOOD TO KNOW. I never seen that kind of T connector.... i used to tune those DECIBEL and Motorola MSF 5000/Qantar duplexer during late 80s to mid 90s I used HP spectrum analyzer and Cushman/Farnell/HP RF signal gen. RF SIGNALGEN IS SET to 0.00 dbm so that I have a direct readind. Initially all rods was set to all up and adjusted one or 2 of the rods until isolation is 90db and other rod to within 3 db insertion loss. I keep on playing also with tuning cap until I got the desired result
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It not clear how these things wire up looks like all are parallel. and I den't understand what capacitor tuning does. Can you explain total wiring
Is this for Ham radio?
I have struggled with cable lengths when tuning duplexers with a tracking generator, (not using a VNA). After tuning a duplexer, if I change the two cables with different lengths, the IFR shows the tuning at different frequencies than first tuned. What is the correct cable lengths used to tune a cavity/duplexer. 300/f x VF x 1/2 wave length?
First, the generator needs to be set up according to the manufacturer’s instructions Second, the test cable lengths should not affect the pass or reject frequencies if the cables and the generator are 50 ohms. The lengths should only change the insertion loss readings and this can be calibrated out (see manufacturer’s instructions). Third, make sure that any unconnected port on the duplexer is terminated in a 50 ohm load. Leaving a port open with definitely throw off the tuning. Fourth, you would need an impedance bridge to set the pass frequency of the cavities. The region of good return loss is smaller than the region for good insertion loss for the pass band so you want to set the minimum reflection for the cavities to the pass frequency.
Do you guys reply to your viewer questions?
yes, we try our best to answer viewers' questions. If you have a specific question regarding Sinclair products, please visit www.sinctech.com/contact/
I wish this video showed a more ordinary test equipment. I don't know what that thing is, but all we use are 2670s with tracking generators...
Any specAn in range with TG would do it. IE 2975 , A3920, HP, Marconi ... anything that has TG. set at ref level 0 and tg 0 and high span and focus in...
go even higher span 10mhz or whatever when searching an existing unknown frequency.
Can the cable assembly be purchased separately? The cables on my Q3220E are damaged and need to be replaced.
Hello! Yes, the cables can be purchased separately. Please contact us at support@sinctech.com or 1 (905) 727-0165.
How do I tune a Q2330e with a HP 8924c? I don't own a network analyzer.
We can’t comment on the proper way to set up a piece of equipment for a given measurement. That would be best be answered by the manufacturer.
Do you hawe 600KHz 145.600MHz -600 shift ?
and what is the price ?
Where abouts are you located? Prices can vary based on currency. Please visit our Sales and Technical Support page for more information: www.sinctech.com/partners/
Who is the manufacturer of that "T" connector, also where can one purchase those "T" connectors from?
The tee connector is just an N type female/male/female tee with the collar cut off of the male end. It save the time needed to screw on and unscrew the connector. The duplexer can be tuned just fine with any standard tee.
I have I bit of a strange case,
personally I don't own the richt tools.. however I do own two identical filters, one came tuned by a professional, the otter I want to tune my self.
equipment I do have: nanoVNA (cheap Chinese tool)
RTL-SDR stick (also cheap Chinese "tool")
SWR-power meter (again, cheap Chinese tool)
now for the fun-part,
I have tuned the filter using the nano-vna, but the dynamic range is poor on those things,..
to get more range u use the nano VNA in CW mode (so It does not sweep, just produce the right frequency) than I use a 10 db attenuator (also cheap Chinese tool) and hook it up to the RTL-SDR and note the exact pont of the signal (frequency and amplitude) note: set the SDR to the smalles sample size since it increases the dynamic range.
add one side of the duplex filter and remove the attenuator.
now the amplitude of has decreased to the noice floor.... but luckily there is a gain in te RTL-SDR
set this to a level you can work with, (not it down) and tweek (very carefully and not by much) the duplexer to minimum deflection! (add gain if needed to allow for signal-noice ratio)
use a cheap radio tuned to the right frequency (pass frequentie) and measure SWR (my measurements came to 1.00 :) )
if both sides are done, you'r done.
im to CHICKEN to use this duplexer right now,
how big is the chance I tuned it completely wrong?
I don't want to blow up my repeaters/radio's
if anybody has an other cheap way to tune filters I would love to hear it :)
73, PD0HOF / PI1HRN (DMR repeater)
Just in case anyone had the same questions. I have tuned them with a nano VNA like yours (Chinese), the Idea is to have two traces in Log Mag (turn the others off). Then for the duplexer port where the TX is going to be connected put VNA CH0 in it and VNA CH1 on the antenna port and the 50homs load on the RX port. Make a Marker for CH0 and another marker for CH1. Goto Stimulus and set the center to the TX frequency (set also the span to your liking). When tunning the cavity look for CH0 and get the best db value, when tuning the notch filter set the center frequency to the RX and adjust the notch until the lowest value is reached (this will depend on the capability of the duplexer). For RX side port of the duplexer, connect CH0 to the antenna port and CH1 to where the RX port of the duplexer, and the 50ohms load to the TX port of the duplexer. Do the same steps above for tuning. If you get good numbers like 1db insertion loss and 70db+ rejection, it is then safe to connect the radios. Make sure you don't mix the ports (Low freq. goes to low port and high freq. goes to high port). Tip, it helps to set the span to a short range in order to zoom in to the graphic. Hope this helps.
This video makes me want to buy Wacom.
why is that?