Re: Suggestions for service monitor
I bought a Motorola R2600C for $600 and then about a week later picked up a Motorola R2550 with tracking generator for $400. I already have a Rigol DSA815TG spectrum analyzer that I use for filter tuning.
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Re: Varden duplexer model# 8D1146B
Could you upload some photos of it?
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Re: Possibly Quintron PA? Need help identifying transistors
Ken, You are likely right but if I had the part number off the board I could confirm. There were some 100 watt mid band boards as well. The coils look different from the UHF ones I have here.?
Ken Pearce? N4KCD? Commerce Township, MI
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On Apr 7, 2025, at 21:49, Ken Arck AH6LE via groups.io <ken@...> wrote:
?
Quintron QT-6700 (UHF) was 90 watts.I have a spare here and his board
looks nothing like the one I have
Ken
At 06:34 PM 4/7/2025, you wrote:
Just looking at it, especially
the LP filter, I'd say UHF...lots of strip line used
Chris WB5ITT
On Mon, Apr 7, 2025, 8:29 PM Tyler- WZ5TX via
<wz5tx=[email protected]
> wrote:
- I have this PA and it is labeled ?�?100W PA?�?.
- However I cannot find the datasheet for the transistors. Motorola
SRF2604.
- any ideas what the range for this is?
- drive needed?
-
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President and CTO - Arcom Controllers
Makers of repeater controllers and accessories
Phone: (503) 678 6182
Authorized Dealers for Kenwood and Telewave.
We offer complete turn-key repeater packages!
"We don't just make 'em. We use 'em!"
![[]](http://www.arcomcontrollers.com/arcom.png)
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Re: Possibly Quintron PA? Need help identifying transistors
Quintron QT-6700 (UHF) was 90 watts.I have a spare here and his board
looks nothing like the one I have
Ken
At 06:34 PM 4/7/2025, you wrote:
Just looking at it, especially
the LP filter, I'd say UHF...lots of strip line used
Chris WB5ITT
On Mon, Apr 7, 2025, 8:29 PM Tyler- WZ5TX via
<wz5tx=[email protected]
> wrote:
- I have this PA and it is labeled ?�?100W PA?�?.
- However I cannot find the datasheet for the transistors. Motorola
SRF2604.
- any ideas what the range for this is?
- drive needed?
-
![[]](/g/repeater-builder/attachment/214406/)
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Content-Disposition: inline; filename="photo-3.jpg"
Content-ID: <[email protected]>
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President and CTO - Arcom Controllers
Makers of repeater controllers and accessories
Phone: (503) 678 6182
Authorized Dealers for Kenwood and Telewave.
We offer complete turn-key repeater packages!
"We don't just make 'em. We use 'em!"
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Re: Possibly Quintron PA? Need help identifying transistors
Need the part number on the other side. Post a pic of the other side. Looks like a Possible mid band board.?
Ken Pearce? N4KCD? Commerce Township, MI
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On Apr 7, 2025, at 21:34, Chris Boone WB5ITT via groups.io <setxtelecom@...> wrote:
? Just looking at it, especially the LP filter, I'd say UHF...lots of strip line used
Chris WB5ITT
I have this PA and it is labeled “100W PA”.
However I cannot find the datasheet for the transistors. Motorola SRF2604.
any ideas what the range for this is?
drive needed?
|
Re: Possibly Quintron PA? Need help identifying transistors
Just looking at it, especially the LP filter, I'd say UHF...lots of strip line used
Chris WB5ITT
I have this PA and it is labeled “100W PA”.
However I cannot find the datasheet for the transistors. Motorola SRF2604.
any ideas what the range for this is?
drive needed?
|
Possibly Quintron PA? Need help identifying transistors
I have this PA and it is labeled “100W PA”.
However I cannot find the datasheet for the transistors. Motorola SRF2604.
any ideas what the range for this is?
drive needed?
|
Re: Amphenol Old Style RG-393?
Looked it up in a Nemal Electronics Catalog, and you remembered correctly, Jeff. Both cables are identical except for the jacket on RG393 is -70 to +200 degree C fluorinated ethylene propylene (FEP) and OD 390 mils. RG225 is -70 to +250 degrees C and fiberglass/ silicone braid and OD 430 mils Both should say Mil C-17D, just a little higher operating temp on RG225.
John
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On 04/07/2025 6:04 PM EDT Jeff DePolo WN3A via groups.io <jd0@...> wrote:
? It is an older variant of RG-393. I know it's 393 and I know it's 50 ohms.
Apparently, I didn’t receive the original post, only your follow-up response. Questions:
1. What is the measured OD of the cable?
2. Does it have a single layer of woven braid for the jacket or two layers?
3. Does it feel like fiberglass or something else like a high-temp polymer?
4. It is actually marked Amphenol and RG-393? Any other markings, part number, etc.?
I’ve seen/used this type of cable in high-temperature and high-power applications; I even have a few jumpers here. What confuses me is that I remember it being larger in diameter than RG-393 (390 mils), and likewise, what I have here at the shop is also larger OD - 430 mils or thereabouts, close to RG-214 if not a hair bigger. What I have here has no markings on it all, but I've always known this type of cable to be RG-225.
Also, I don’t remember ever seeing any marked as RG-393, so that’s why I asked about what is printed on your cable. I do have some old Amphenol catalogs around somewhere, but in the meantime, look up RG-225 to see if that’s close to what you have.
--- Jeff WN3A
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Hi Greg,
?
Several things from the school of hard knocks...? Recheck the length of your VB-35 matching section with at least several feet of 50 ohm coax between it and your measuring instrument as I found it was different if directly connected to a tower mounted diplexer N female input, than if a length of 50 ohm coax in the middle. I do not have a DB cutting chart, but have a few more DB lengths. DB said for 53.23 MHz, the length of VB35 should be 36 5/8 inches. I have a note that for 52.8 MHz the distance from open end of the N female to the UHF barrel tightening ring should be 37" so that includes the UHF barrel. So you must be close and as you said tuning is broad.
?
If you are using the end supports to the tower leg placed out 2/3 on the element ,for 53.1 MHz 1.02SWR, top to metal center support top is 49 3/8", bottom tip to metal center support bottom is 50 3/8" (our test set-up on a tower leg free and clear)
?
We found the factory? N connectors pulled apart with tower icing and high winds, so I went to 2 piece N connectors, but if you used thick wall heat shrink like used for underground? electrical wiring, on your T and N connector, you should be OK.
?
John
On 04/07/2025 5:55 PM EDT 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.
?
Mike,
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?
Greg
WB9TRO
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Re: MTR2000 channel steering
Such as? The RSS is pretty easy to navigate?
Chris WB5ITT?
Thanks for your input, however I'm looking for help programming the MTR2000 instead of a functional description.
73
-de John NI0K
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Re: Suggestions for service monitor
I second this. I had the same question about a month ago and ended up getting an HP8921A. It’s a good analyzer to learn on and does probably way more than you need.?
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On Apr 7, 2025, at 6:42?PM, Mike via groups.io <prcradio@...> wrote:
? For non digital stuff the HP/Agilent 8920 series.?
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Re: Suggestions for service monitor
For non digital stuff the HP/Agilent 8920 series.?
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Re: Suggestions for service monitor
The NanoVNA-V2 seems to handle doing the pass part pretty well. You're measuring return loss there, and it seems to handle that just fine. Only question I might se is if the frequency standard is really accurate enough to set it correctly-but I bet it's pretty close...
Notches on the other hand-forget it. Definitely not even close to enough range for that. Even most service monitors can't do it, or are right on the edge of doing tolerably.
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On 4/6/2025 5:34 PM, Bob Dengler via groups.io wrote: At 4/6/2025 01:35 PM, you wrote:
Ooh this is interesting. I have a NanoVNA and I think I asked here and also saw some other threads here that were saying its dynamic range is not enough to tune a duplexer. LibreVNA looks a lot more capable! I've seen reports of drift issues with the LibraVNA.? For the moment I'm happy with my VNWA 3EC (though the design is getting dated so not sure I'd recommend for a new purchase), but if I needed one today I'd try this one: < <>>
Bob NO6B
_._,_._,_
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Re: Amphenol Old Style RG-393?
? It is an older variant of RG-393. I know it's 393 and I know it's 50 ohms.
Apparently, I didn’t receive the original post, only your follow-up response. Questions:
1. What is the measured OD of the cable?
2. Does it have a single layer of woven braid for the jacket or two layers?
3. Does it feel like fiberglass or something else like a high-temp polymer?
4. It is actually marked Amphenol and RG-393? Any other markings, part number, etc.?
I’ve seen/used this type of cable in high-temperature and high-power applications; I even have a few jumpers here. What confuses me is that I remember it being larger in diameter than RG-393 (390 mils), and likewise, what I have here at the shop is also larger OD - 430 mils or thereabouts, close to RG-214 if not a hair bigger. What I have here has no markings on it all, but I've always known this type of cable to be RG-225.
Also, I don’t remember ever seeing any marked as RG-393, so that’s why I asked about what is printed on your cable. I do have some old Amphenol catalogs around somewhere, but in the meantime, look up RG-225 to see if that’s close to what you have.
--- Jeff WN3A
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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.
?
Mike,
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?
Greg
WB9TRO
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Re: Amphenol Old Style RG-393?
I don't think you understood my question...I am asking about this specific cable. It is an older variant of RG-393. I know it's 393 and I know it's 50 ohms. I'm aware of every RF connector. I'm looking for information on this specific style of 393. The internet is of no help on this cable. Termination is definitely different than the solid FEP because of the braided sheath. Obviously need to keep it from unraveling itself.?
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Varden duplexer model# 8D1146B
Hello all, would anyone have any tuning information on the Varden duplexer 146-148mhz. I know its a long shot, but no searches on the web produced any results.?
?
These were made by
Varden Electronics
Box 791, Jackson, Michigan
49204
?
Thanks for any information
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Re: Amphenol Old Style RG-393?
Internet has all your info, its 50 ohm and would be great for jumpers between a repeater and other stuff. Connectors are available in many types.?
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Re: 220Mhz ACSB amplifier
AH6LE,
?
Ken,
?
I wonder if? some of the same UPS AT 220 MHz amps may show up at the next Rickreall hamfest, I missed the one at Rickreall this Feb.? but maybe the one in the fall could have some available?
?
I don't remember the call of the guy who sold them to me either so it's probably a stretch hoping for some of them to show up at the Swaptober hamfest near Salem but it's worth the try.
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Re: 220Mhz ACSB amplifier
Mine didn't have any fans and no? cases on any of these amps either but they were complete and the box was marked as working 220 MHZ ACSSB amplifiers.
?
The amps all included the T/R switch, a low pass filter and bias circuitry and the same 3 transistor Motorola RF lineup.
?
An entire box of several amps was purchased back in 2013 at the RickReall Oregon hamfest from an unknown seller for only 50 dollars along with a? working ~180 watt TPL 220MHz amp.
?
The UPS/AT 220 amps were all ~ 50 watts output and most had no markings but 2 were marked? UPS AT, Salem Oregon but all of them have the same RF board design with Motorola TMOS devices in them.
?
I have used 2 of these amps with a 220 home brew Wilkinson combiner in my 220 MHz to 10 FM FM remote base system for the past 12 years without a failure, the others are spares just in case I have failure.
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Jared Smudde
Ken Arck AH6LE
Chris Boone WB5ITT
Tom VA3TS