Re: PD526 Duplexer Tuning
Ok, I'm tuning the pd526 on the nvna. I can't seek to get everything to line up on both reject and pass simultaneously. It seems to be one or the other. I have attached pic of my latest plot. This is the best I got it so far. I did tune cavities individually then hook them together. And I got multiple peaks and valleys on the plot instead on one nice peak on the pass and valley on the reject. Does anyone have a link to the plot for the pd526 and what it should look?like?
Thanks 
I think I finally got the pd526 tuned. It has 1db difference in sensitivity between direct input and going through duplexer and very little tx power loss coming out of duplexer. Probably only a few watts of loss. Tomorrow I will do some field testing to see if it gets put as far as the txrx 28-70-15h duplexer I was using. I'm not seeing any signs of desense yet.
It will have the opposite effect.? To get more dynamic range you would really need an amplifier or a way to drive in more signal.? The pads are just to match the impedance as the output/input terminals may not be the nominal 50 ohms.? That is just for the notches.? If tuning the pass with a RLB do not use a pad as this will give a false match/very low RL .
Ralph ku4pt
On Thursday, April 24, 2025 at 11:28:09 AM EDT, Part 15 Engineer via <kc8gpd= gmail.com@groups.io> wrote:
Will a pad give the nanovna more of a dynamic range to see? the notch depth? Iirc the dynamic range of a standard nvna is about 60 to 80db. So if I put a 10 or 15db pad that should help with tuning the notches?
Pads can be helpful on the generate side of a VNA providing a good resistive match to the device under test. Many years ago working at Hughes Aircraft we always terminated our generate cables with a 6dB pad.?
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Re: Motorola gp340 as echolink node
Forgot to reply,?
?
Everything works, thanks Duane.
Echolink is up and working great!
?
73
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Re: Astron RM-50M conversion
So the IOTA DLS-45 w/IQ4 LiFePo module will do this:
Charge at 45 amps (the limit) with a target voltage setpoint of 14.7 volts. When it detects 14.6 volts OR 240 minutes in this mode has elapsed, it will then continue in this mode for 15 more minutes, then switch to float mode. Float mode is an attempt?to hold a constant voltage of 13.6 volts (up to the 45 amp limit of the charger). If the voltage drops below 12.8 volts OR 15 days elapse, it starts over at the beginning.
Assuming your two isolation diodes are identical, and assuming zero loss in the LVD (most MOSFET-based LVDs are essentially zero voltage drop, as are all relay-based ones) and assuming a 13.8 volt "DC supply" as the secondary source, the following happens:
1. When the batteries are low, the IOTA outputs (up to) 14.7 volts, which exceeds the voltage of the supply. The moment the batteries charge to the point where the voltage across them exceeds 13.8 volts, some of the charge current is diverted to your load (at up to 14.7 volts minus the voltage drop of the isolation diode). Once the voltage across the batteries reaches 14.6 volts or 240 minutes has elapsed -- then -- 15 minutes later... 2. The IQ4 will drop the target voltage to 13.6 volts, but the battery voltage will exceed your DC supply voltage for a while and the battery will power your load as it discharges from completely full. It'll "share" with the DC supply, but because the voltage is higher, the majority of the load current will be drawn from the batteries until they are drained to 13.8 volts. Fortunately, a LiFePO4 battery is still roughly 90% full, maybe more, at that voltage, so you haven't lost *that* much capacity. At that point, current is shared between the battery and the DC supply, and shortly thereafter the battery stops providing any useful power because its voltage (minus the blocking diode drop) is lower than the 13.8 (minus its blocking diode drop) and the DC supply takes over the load completey. 3. The batteries then sit doing nothing at a float voltage of 13.6 volts... because there's no load on them, they'll never go below that, and 15 days later the cycle repeats from the top whether the batteries need it or not.
If/when there is a power outage, the batteries, which should be *mostly* charged up by that 13.6 volt float voltage, take over and power the load until the LVD trips off. Once power returns, the above cycle starts at the top. If 45 amps divided across the four batteries for 240+15 minutes isn't enough to fully charge them back up after the outage, they'll just slow charge at the trickle rate after that... so hopefully you don't get another outage soon.
Note that the Battle Born 12v battery will disconnect at >14.7 volts, so hopefully the IQ4 doesn't actually go any higher than that. It will also disconnect at <10.6 volts but if you don't reboot it soon it is hard to recover, so you want your LVD set higher than that.?
Matthew Kaufman
Good points. Trying to capture this graphically as things progress.? Attached JPG... a) choose your battery and appropriate charging technology b) isolate battery from mains supply of choice... (D1 and D2) b.1) perhaps to further isolate the batteries and mains 'conflict'... apply multiple 'D1' in series - enough to establish the differential between their voltages so the batteries are not taking load (as their voltage is presented lower via D1(s)) when mains source is available c) I'm not much in favor of the mains vs battery relay option...? prefer not dropping power to the rack gear and restoring in a cut-over if it can be avoided.? Depending on what's in the rack, some things don't recover well if at all - Pi-based devices for one. d) not going to be perfect +/- either battery technology... preferably leave them out of circuit as much as possible unless/until needed and can 'gracefully' take the load, and otherwise not be over- or under-charged.? ? ?"hard floating" lead acid is/was probably OK if you have the budget and mindset to check and rotate them out.?? It's possible in my evolution of all this I give up on the LiFePo options and just do what I can with the remaining former data center UPS AGMs I have - at 97# a piece. 
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Re: Difficulty Programming a Maxtrac 300, 32 Channel
I got a bunch of HP thin clients with real serial ports on them that I use freeDOS on. It just works. All DOS based programming apps have worked with issue. They are 12V too!
Contact me direct if you want one. $20 plus ship.
Benjamin, KB9LFZ?
For DOS on modern PC's, I had success when faced with many failures to run RSS for HT1000's, MT1000's and similar so far work
Made a bootable USB stick (used a spare 8Gb that was around) and loaded FreeDOS on it following online references for how to do this. Changed the boot order for the windows 7 toughbook I use for programming and it works without any issues - like scary how well this replicated having a 286 laptop 20 years ago running RSS
Notes - PC cannot be UEFI bios. You should only use with a PC that has a native serial port - not seeing a likely to have this port to a USB serial device.
Jason
I run VMBOX on Win10...load XP SP3 32BIT on the VM box..it can run anything you need
Chris WB5ITT?
Jared
Do you have just one Maxtrac that you want programmed??? or do you have a shelf, box, or storage room full of them ?? what band Maxtrac do you have?
L/B, VHF, UHF, 800, 900? and what would you like to put in them?
if its just one then maybe someone out here can help you. There are still some of us running 386 computers (collecting dust most of the time)
You can always look for an older Panasonic Toughbook, they have a real DB9 comm port (com 1) along with a single usb port, load DOS 6.22 and then load the Maxtrac or Maxlab software, hook up the RIB box & Cable & have fun,
Bob KD6GNB
On Sunday, April 20, 2025 at 10:45:40 AM PDT, Jared Smudde via <computerwhiz02= hotmail.com@groups.io> wrote:
I’ve made numerous attempts to use DosBox over the years and have never had any luck. I’ve got a 486 laptop that I use for DOS software and before that I used to program them with a 2007 dual core AMD processor running FreeDOS off a USB drive. The only issue I’ve had with processor speed is the R100 software and the Radius M10 software.?
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Re: Motorola SLR5700 DMR Repeater
The beacon transmitted on Mototrbo systems is primarily for Roaming and that's where a radio makes a decision which repeater to use based on the strongest beacon. Similar to voting in other systems, except in a voting system, the repeater makes the choice, not the radio. We Don't do roaming in ham and another thing about having beaconing turned on, especially set to transmit every 60 seconds, it keeps the cooling fans wound up at high speed 24/7. Not to mention cluttering the air ways with unnecessary RF. We have ours off!
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Re: Motorola SLR5700 DMR Repeater
On 4/25/2025 3:26 PM, Chris Boone WB5ITT via groups.io wrote: Beaconing 24/7 is permitted outside the automatic beacon subbands ONLY IF a control operator of the repeater xmtr, NOT the network, is monitoring the actual RF channel to prevent interference.. geese why do people NOT READ THE RULES? sorry folks but part 97 is part 97. ..if you can't follow them, turn in your license and go back to 27MHz or GMRS.
If you think this is wrong, ask Riley or Laura...they've both sent notices to repeaters beaconing IDs , etc.
Chris WB5ITT
On Thu, Apr 24, 2025, 7:31?PM bob ehrhorn via groups.io <> <behrhorn@... <mailto:pacbell.net@groups.io>> wrote:
Hi guys
The SLR5700 has a beacon that it transmits in DMR mode so the mobile
and hand held units can synchronize the TDMA time slots and know
there within range of the repeater???
***And you should turn it off.
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Re: Astron RM-50M conversion
Sure, but no "13.8 volt regulated supply" will be *higher* than the bulk charge or equalization voltage (in excess of 14 volts) for an AGM charger.
Matthew Kaufman
> The battery-specific charger still sees the load (albeit via a voltage drop from the diode).
Only if the charger/battery combination are higher voltage than the power supply output, assuming equal voltage drop across the diode block.? As long as the power supply voltage is higher, the battery backup system remains isolated from the load.
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? --- Jeff WN3A
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Re: Motorola SLR5700 DMR Repeater
Beaconing 24/7 is permitted outside the automatic beacon subbands ONLY IF a control operator of the repeater xmtr, NOT the network, is monitoring the actual RF channel to prevent interference.. geese why do people NOT READ THE RULES? sorry folks but part 97 is part 97. ..if you can't follow them, turn in your license and go back to 27MHz or GMRS.?
If you think this is wrong, ask Riley or Laura...they've both sent notices to repeaters beaconing IDs , etc.
Chris WB5ITT
Hi guys
The SLR5700 has a beacon that it transmits in DMR mode so the mobile and hand held units can synchronize the TDMA time slots and know there within range of the repeater???
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Re: Need help on the Quantar test microphone
Or bring them with you to Hamvention Jeff.
Gary
toggle quoted message
Show quoted text
From: repeater-builder@groups.io <repeater-builder@groups.io> on behalf of Jeff DePolo WN3A via groups.io <jd0@...>
Sent: Friday, April 25, 2025 6:38 AM
To: repeater-builder@groups.io <repeater-builder@groups.io>
Subject: Re: [repeater-builder] Need help on the Quantar test microphone
?
- Also same mic as the Mostar,
Traxar snd MSF5000.
?
I think I have some Mostar mics somewhere.?
Those had the “flat” coiled cord if I remember right.?
If the OP needs one, email direct and I’ll see if I can find one.
?
???????????????????????????????????????????????????????????????????????????????
--- Jeff WN3A
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Re: Difficulty Programming a Maxtrac 300, 32 Channel
For DOS on modern PC's, I had success when faced with many failures to run RSS for HT1000's, MT1000's and similar so far work
Made a bootable USB stick (used a spare 8Gb that was around) and loaded FreeDOS on it following online references for how to do this. Changed the boot order for the windows 7 toughbook I use for programming and it works without any issues - like scary how well this replicated having a 286 laptop 20 years ago running RSS
Notes - PC cannot be UEFI bios. You should only use with a PC that has a native serial port - not seeing a likely to have this port to a USB serial device.
Jason
I run VMBOX on Win10...load XP SP3 32BIT on the VM box..it can run anything you need
Chris WB5ITT?
Jared
Do you have just one Maxtrac that you want programmed??? or do you have a shelf, box, or storage room full of them ?? what band Maxtrac do you have?
L/B, VHF, UHF, 800, 900? and what would you like to put in them?
if its just one then maybe someone out here can help you. There are still some of us running 386 computers (collecting dust most of the time)
You can always look for an older Panasonic Toughbook, they have a real DB9 comm port (com 1) along with a single usb port, load DOS 6.22 and then load the Maxtrac or Maxlab software, hook up the RIB box & Cable & have fun,
Bob KD6GNB
On Sunday, April 20, 2025 at 10:45:40 AM PDT, Jared Smudde via <computerwhiz02= hotmail.com@groups.io> wrote:
I’ve made numerous attempts to use DosBox over the years and have never had any luck. I’ve got a 486 laptop that I use for DOS software and before that I used to program them with a 2007 dual core AMD processor running FreeDOS off a USB drive. The only issue I’ve had with processor speed is the R100 software and the Radius M10 software.?
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How many in a Chinese dozen???
This is only a test
Test ? Attached is some information on the DB212 antennas.? Perhaps this will help.? This was factory info from a DB212-2 that was tuned to 47.14 MHz. 73 Joe WB4HIS ? ? ? ? Roger,
In hopes of answering your original question, I got my hands on a DB212-2 originally on 37.7MHz and shortened the antennas and matching section for 6?
meters. The 35 ohm matching section (Decibel Products VB-83 cable) was shortened?
to 36.25" end to end. With a UHF T on the end?
and two 50 ohm loads attached resulted in the attached plot. As you can see, the?
exact length is not critical across the band. John,
You mentioned "DB factory lengths" in an earlier post. Do you have access to the?
actual factory length chart for 6M ? If so, please share. How well did the tuning of your antenna on the ground translate to mounting on a tower? What length of pipe did you use when tuning? <6meter DB212-2 matching section.png>
<DB212-2 Information.pdf> <DB212 (pg 6-7).pdf>
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Re: Need help on the Quantar test microphone
- Also same mic as the Mostar, Traxar snd MSF5000.
? I think I have some Mostar mics somewhere.? Those had the “flat” coiled cord if I remember right.? If the OP needs one, email direct and I’ll see if I can find one. ? ??????????????????????????????????????????????????????????????????????????????? --- Jeff WN3A
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toggle quoted message
Show quoted text
On Apr 8, 2025, at 9:43?AM, Joe Poerschke via groups.io <wb4his@...> wrote:
? Attached is some information on the DB212 antennas.? Perhaps this will help.? This was factory info from a DB212-2 that was tuned to 47.14 MHz. 73 Joe WB4HIS ? From: repeater-builder@groups.io [mailto:repeater-builder@groups.io] On Behalf Of Roger willey via groups.io
Sent: Tuesday, April 8, 2025 09:28
To: repeater-builder@groups.io
Cc: repeater-builder@groups.io
Subject: Re: [repeater-builder] 6 m repeater antenna ? ?
On Apr 7, 2025, at 5:55?PM, wgwl via groups.io <wgwl@...> wrote: ? Roger,
In hopes of answering your original question, I got my hands on a DB212-2 originally on 37.7MHz and shortened the antennas and matching section for 6?
meters. The 35 ohm matching section (Decibel Products VB-83 cable) was shortened?
to 36.25" end to end. With a UHF T on the end?
and two 50 ohm loads attached resulted in the attached plot. As you can see, the?
exact length is not critical across the band. John,
You mentioned "DB factory lengths" in an earlier post. Do you have access to the?
actual factory length chart for 6M ? If so, please share. How well did the tuning of your antenna on the ground translate to mounting on a tower? What length of pipe did you use when tuning? <6meter DB212-2 matching section.png>
<DB212-2 Information.pdf> <DB212 (pg 6-7).pdf>
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Re: Need help on the Quantar test microphone
Also same mic as the Mostar, Traxar snd MSF5000.
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Hi Brian,
?
I see you have met my buddy Lane recently. ?I recognize one of the photos, and I especially recognize the Millennium modules. ?I actually have one of the 8-10 DXRS chassis here in Louisiana, since I kept one of them instead of sending them all back to Virginia with Lane this past February, with the other inventory he came down here to retrieve. ?;-) ?
?
The DX Radio Systems "Millennium" equipment originally came my way when I started playing "Storage Wars" a couple of years ago, and purchased a large 10x30 unit that was completely full of commercial radio equipment that had been owned by a large communications company in Dallas, TX. ?They were in business from 1991-2012 and had the DFW area completely covered, offering repeater service on VHF, UHF, and 800-900MHz LTR trunked communications and NexTel cell service for medium sized companies to extremely large corporations.
?
That being said, I never was able to determine actual service dates for the DXRS stuff. ?And I guess I didn't really dig into it as much as I should've. ?Because I never looked closely at the PA units to determine the the manufacturer. ?There were around 80-90 amplifiers in that unit and I do recall that at least 3-4 of the 900MHz 150w amps were made by Crescend. ?Because I still have two of those (Crescend P15-R2L1-Cx-001) units here (1 active and 1 backup). ?They were originally rebranded and sold by Kenwood.
?
But getting back to the units you have, I don't know if this will help you or not. ?I have the DXRS Millennium SystemConfig and Repair Documentation. ?I had been trying to get it converted to Digital format (PDF), but had been unable to complete the job until earlier this evening. ?My architect buddy (with the high speed duplexing scanner/copier/printer) has been battling kidney stones for the past 2-3 weeks. ?So everything went "on hold" for awhile. ?But today he began feeling better and called me to come by the office and bring the hardcopy manual. ?
?
I just sent a digital copy to Lane about an hour ago. ?He had been waiting on that since mid-March and was very happy to get it. ?It's about 6-8 chapters long and (the original hardcopy) fills up a 1"-1.5" 3-ring Binder. ?I've glanced through it and I know that it has all the info needed for diagnosis of problems, tuning and alignment procedures, etc. along with schematics as well. ?So it may possibly give the info on the PA module as well. ?Therefore you are welcome to a copy of it if you like. ?I'm not sure of the rules and procedures for uploading to the file area here, so if it ends up going into the wrong place, please forgive me in advance.
?
David Tucker
N5ZDT
?
PS-DX Radio Systems went out of business a number of years ago as I understand the history. So I doubt that the material would classify as a copyright infringement problem. ?Let me know if this does NOT make it to you. ?
?
?
?
?
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Re: Astron RM-50M conversion
FWIW - RV 12v loads are becoming more and dynamic - on shore-power or off.??
Pump for on-board stored water.? The LP-fired furnace fan.? Some/many builds are moving to 12v refrigeration (Peltier effect or other?)? For some reason some many folks are using their on-board 12v to 120v AC inverters... terribly inefficient power hogs - maybe consumers don't know they can get 12v charging adapters for their laptops, devices or even 12v operated TVs.??
At practical best maybe you get 600-800w of solar panels on the roof.? I've got 400w.? Being frugal with power use, boon-docking at Quartzite (popular with hams) or other desert destinations - usually good sun most of the time ... doing good to get 3-4 days before pulling out the generator to top off from the AC-driven charger.
The typical build by most Airstream 'upfitters' is to do solar, Victron charge controller, BattleBorn... and leave the original mains-driven conventional AGM-supporting supply/charger in-circuit not isolated or switched between.? Forget to or cannot plug in when you store your rig... No LVD until the BattleBorn pack drains and shuts off.? ? That's when you freak out at 'losing' $1600-2000 worth of new batteries, until BB tells you how to recover them.??
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Re: Astron RM-50M conversion
Good points. Trying to capture this graphically as things progress.? Attached JPG... a) choose your battery and appropriate charging technology b) isolate battery from mains supply of choice... (D1 and D2) b.1) perhaps to further isolate the batteries and mains 'conflict'... apply multiple 'D1' in series - enough to establish the differential between their voltages so the batteries are not taking load (as their voltage is presented lower via D1(s)) when mains source is available c) I'm not much in favor of the mains vs battery relay option...? prefer not dropping power to the rack gear and restoring in a cut-over if it can be avoided.? Depending on what's in the rack, some things don't recover well if at all - Pi-based devices for one. d) not going to be perfect +/- either battery technology... preferably leave them out of circuit as much as possible unless/until needed and can 'gracefully' take the load, and otherwise not be over- or under-charged.? ? ?"hard floating" lead acid is/was probably OK if you have the budget and mindset to check and rotate them out.?? It's possible in my evolution of all this I give up on the LiFePo options and just do what I can with the remaining former data center UPS AGMs I have - at 97# a piece. 
|
Re: PD526 Duplexer Tuning
I think I finally got the pd526 tuned. It has 1db difference in sensitivity between direct input and going through duplexer and very little tx power loss coming out of duplexer. Probably only a few watts of loss. Tomorrow I will do some field testing to see if it gets put as far as the txrx 28-70-15h duplexer I was using. I'm not seeing any signs of desense yet.
It will have the opposite effect.? To get more dynamic range you would really need an amplifier or a way to drive in more signal.? The pads are just to match the impedance as the output/input terminals may not be the nominal 50 ohms.? That is just for the notches.? If tuning the pass with a RLB do not use a pad as this will give a false match/very low RL .
Ralph ku4pt
On Thursday, April 24, 2025 at 11:28:09 AM EDT, Part 15 Engineer via <kc8gpd= gmail.com@groups.io> wrote:
Will a pad give the nanovna more of a dynamic range to see? the notch depth? Iirc the dynamic range of a standard nvna is about 60 to 80db. So if I put a 10 or 15db pad that should help with tuning the notches?
Pads can be helpful on the generate side of a VNA providing a good resistive match to the device under test. Many years ago working at Hughes Aircraft we always terminated our generate cables with a 6dB pad.?
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Re: Motorola SLR5700 DMR Repeater
Hi guys
The SLR5700 has a beacon that it transmits in DMR mode so the mobile and hand held units can synchronize the TDMA time slots and know there within range of the repeater???
|
KB9LFZ
Chris Boone WB5ITT