MSF5000 repeaters in 900mhz - any interest?

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Mastertech
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Mastertech »

Well, after spending plenty of time tweaking and tuning I finally got the receiver working the way it should. At this point I can key the machine at .088 Microvolts!!! very hot, though I may need to cool it down a little once it gets to the site. However, I do have a deviation question for the MSF experts out there. I can't seem to get the machine to pass 2.5 KHz, the best I can do is 1.6-,1.7 with 1volt-rms into TP8 at the mic plug and that’s with the max deviation epot set to 99. Obviously I'm missing something here, is there some other trick to get the deviation up where it needs to be? Any input is much appreciated
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n9wys
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

I thought 2.5 was the proper deviation for 900 MHz... I know that some of my mobiles can do around 4.5 to 5, but IIRC 900 is "narrowband" and so 2.5 is the correct max level.

At least I have mine set at about 2.4...
Mark - N9WYS
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Mastertech »

Hey Mark, thanks for the reply. Yes, 900 is narrow band (at least in the commercial region) and this means we should be looking for max deviation of 2.5 Khz. My problem is that when I key the machine and inject the required 1v rms 1k tone into TP8 I can only get the machine to show 1.7 Khz dev. with the dev epot at its max setting... I was wondering if there is anything else I'm missing when trying to set the max deveation, perhaps because these were trunking machines there are some extra steps im not aware of?
Last edited by Mastertech on Tue Mar 25, 2008 1:46 pm, edited 1 time in total.
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n9wys
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

Don't know about that... When I went through the alignment procedure, everything came into spec for me. IIRC, my Deviation EEPOT is set at "68" or "69" to give me 2.4 kc deviation. Maybe if you're trying to overdrive it, it has some sort of cutback/fallback circuit to compensate? (Shooting in the dark now...)

Are you sure you don't have a cut leg on U831? That was the EEPOT (I think) that was "modified" for trunking operations, but needs to be whole for repeater ops. I'm not sure how the cut leg affects repeater operations - or if it allows operation at all if modified - but thatmight be a place ot start. Fortunately, of the three stations I acquired, only one had this "mod" performed - and right now I'm using that one for parts...
Mark - N9WYS
Mastertech
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Mastertech »

hey Mark, I actuially replaced U831 with a part that I got off the board here when guys were talking about that issue, so i think that part should be ok at this point..... If I read the posts correctly, cutting that leg disabled some type of audio feature to pass upon transmit. Perhaps, the part number listed here is not correct and I have installed the wrong IC?

However, at some point, someone place a little cap piggie-backed onto one of the IC's on the SSCB. (ill provide detalis when im back home with the machine) Whoever did it did a nice job, but I have not a clue what that mod was for and I have heard no one else talk about it. I wonder if thats something I should look into. I may call moto today and see If I cant get more info on that mod. As far as the allignment procedure, my manual only includes the older style station controller, not the newer style like ours. The problem is that most of the settings are real pots on those older controllers. Is there some place I might be able to find the allignment procedure for our model of station?
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w2ymm
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by w2ymm »

Is there some place I might be able to find the allignment procedure for our model of station?
Have you taken a look here for the manual ?http://www.repeater-builder.com/motorol ... -align.pdf
I haven't completed mine yet, but found some good info.
Bob P W2YMM
Robert Prybyzerski Jr
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Mastertech
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Mastertech »

Oh wow, cool thanks man. This has what I was looking for, and the info that I needed.
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Mastertech »

Well problem solved! As it turns out I had a little cap soldered onto the back of IC U814, I believe onto pin 7 and 10. Once I removed this I was able to get 2.5 khz Deviation with no problem when I injected 1vrms into the station with a 1khz tone. Moreover, I tried keying the station without the programming cable plugged in; rather, I brought TP 9 to ground to key it up. I find that the when the programming cable is plugged in the TX deviation goes way way down. So, I simply adjusted that EEPot from the front panel control. I am not sure why the deviation goes down with the programmign cable plugged in, but it does it every time. After doing some research I found that U814 is involved in the TX audio, however, I dont yet know how. Either way, with that cap in place i could not get the correct deviation out of the station. I think now it's time to get the unit up to the site and give this ole thing a test drive on the 900 band.

The machine Will be located near the Westchester County Airport, The PL will be 114.8 and Ill post the pair as soon as I am sure where it will be.

Thanks to every one for their help

Mark. KG2NB
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rrfd43
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by rrfd43 »

Got a interfacing question with these machines:

I'm trying to interface an echolink computer local at the site. I have tried the local mic with poor audio results. I switch to the MRTI and just can't and seem to get the audio in at all. The recive audio is routed to the computer but is is "choppy".

I have set up the station as a basic repeater using the internal controller. I have the repeater as primary ptt, then mrti as second, local last. MRTI is enabled. The mrti keys the station up and you can barley hear the audio, if at all. I am making my own interface: between the soundcard and machine I have 600:600 audio transformers. Should I change to a 1.2k to 8 transformer on the audio in to the repeater?

Any ideas? I have read the repeater builder site a number of times, but am comming up short on what to do.
Mastertech
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Mastertech »

Hey Man, look at the Zetron model 38A repeater controller manual, It talks about there to get all the stuff you need to inteface an external control. Perhaps you might find some good info there. Good luck.
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kcbooboo
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by kcbooboo »

Most of the Echolink and IRLP implementations were designed to operate with Japanese radio's MIC input levels and impedances, which are typically greater than 1000 ohms and rather sensitive: a dozen millivolts or so.

Most Motorola radios (MaxTrac, GTX, MSF, etc) have a 600 ohm MIC or LINE input impedance and expect a lot of signal level: hundreds of millivolts.

A transformer MAY help with the impedance, but you'll still need more level than most interconnects are willing to provide.

You have to enable the MRTI input on one screen in addition to including it in the PTT Priority list.

Many years ago when I first starting playing with MSF interfacing, I found that some of the signals I was using - related to the COR or RXSTAT - changed their operating polarity if I had the station set up as a repeater vs a base station. Things seemed to work fine in one configuration but not in the other. I eventually set the station as a base station, used an external controller, and never had any problems after that.

Bob M.
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redbeard
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by redbeard »

Me and another guy made some adapters to convert the pin outs from a Maxtrac handset to the 6 pin MSF jack. Neither of us could get them to work. No audio out, no transmit. Nothing. Any ideas why? Seems like it would be a quick and dirty way around having a metering panel for some basic testing.
Look, it's not in my nature to be mysterious. But I can't talk about it and I can't talk about why.
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Doug »

Is local in the list for ptt priorities?
May the Schwarz be with you.
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redbeard
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by redbeard »

Probably not, but that was the other reason to build this adapter...to adapt my Maxtrac cable to the MSF for programming. I still haven't found a 6 pin cable yet to make a dedicated cable. Would that affect being able to hear receive audio on the handset though?

When I find a completely populated cable to connect from my adapter to the MSF, I will read it and see if local is in the PTT list. I was thinking it was a voltage issue, where the MSF doesn't have a bias on one of the lines the handset needs to operate. A standard Maxtrac hand mic doesn't work either but that may be a programming issue obviously.
Look, it's not in my nature to be mysterious. But I can't talk about it and I can't talk about why.
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by WB6DGN »

I'm still looking for a few parts for a 900Mc MSF if anyone is parting one out. I need the SSCB, a 900Mc. Uniboard and, preferably, a TTRC. If anyone has a spare that they're willing to part with, please let me know. My email is tallinson2 <at> yahooo <dot> com. Thanks,
Tom KB5DPE
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redbeard
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by redbeard »

Drive to Jersey... I gave very little for one of the machines considered 'parts' and there was really nothing wrong with it.
Look, it's not in my nature to be mysterious. But I can't talk about it and I can't talk about why.
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by WB6DGN »

Drive to Jersey
WISH I COULD! I'd be bringing back more than just a parts radio! Medical issues don't allow me to drive right now; that's why I'm checking on the board every now and then.
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by ayaresr »

Does anyone know the pinout for the metering jack? I got a panel and the only cable with it was the ribbon cable, so I am looking for the 6 or 8 pin (can't remember which) pinout that is used for the RX and TX meter jacks on the front of the RF tray. I am tempted to think its probably straight thru, but wanted to ask before just trying something. Also, the blue adapters that were on the side (similar to a console to rollover cable from a firewall), were they used to interface these to the trunked system, or something else...without looking I want to say it was on J2.
Thanks, Ryan
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Doug »

May the Schwarz be with you.
ayaresr
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by ayaresr »

Thank you for the link...that will get me moving again.
Ryan
P.S. If anyone's interested one of my two stations will be on air on the outer edge of Wilmington, DE as soon as I get it setup. Still working on the other, more than likely it will end up near the border of Salem and Gloucester Counties toward Franklin Township. That one is more a back burner project for the moment.
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by fineshot1 »

ayaresr wrote:Thank you for the link...that will get me moving again.
Ryan
P.S. If anyone's interested one of my two stations will be on air on the outer edge of Wilmington, DE as soon as I get it setup. Still working on the other, more than likely it will end up near the border of Salem and Gloucester Counties toward Franklin Township. That one is more a back burner project for the moment.
If you could please pass along the freq pairs, tones & locations so us local folk could program our radios for your pairs and you may wish to publish them in the AR902 list.
- tnx...
fineshot1
NJ USA
ayaresr
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by ayaresr »

As soon as I am certain of locations I will be in touch with the coordinator and will post when I have frequencies.
Ryan
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

Well, everyone... I haven't fallen off the face of the Earth - I'm just taking things slow and easy with this station.

My duplexer should arrive today and once I get that "plumbed in", all I'll need to do is put the cabinet cover back on and drag it to the tower site. So far, my conversion has been going pretty easily... I hope the installation and operation go as easily.
Mark - N9WYS
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w2ymm
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by w2ymm »

Hey Guys, I was wondering how you all ended up interfacing a duplexer to the MSF.
Mine right now is mounted to an L bracket I welded together sitting on top of the unit.
I have LMR-400 from the TX and RX ports up to the duplexer.

I was wondering if anyone did any rearranging of the cabinet and was able to
sneak one inside, And how you did it.
I may try to squeeze my Wacom WP-687-3943 inside.

If any one wants to share, I'd like to hear :lol:
Thanks
Bob P W2YMM
Robert Prybyzerski Jr
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n9wys
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

Regarding mounting a duplexer -- I bought some 2" angle aluminum and made an offset bracket for mine... (The duplexer tuning knobs stick out in front and the cans in the back, so mounting it flush wouldn't allow me to get the door back on.) I needed 2" angle in order to offset it far enough into the cabinet (the actual distance was 2 3/8"), but I had to cut an inch off each flange where it bolts to the duplexer and the rack. I ended up dropping the RF tray as low in the rack as I could and then mounting the duplexer above that. Had to re-plumb some of the antenna cabling in order to get the RX, TX and antenna going in the right directions, but so far - so good. I took some photos - if anyone is interested I can try to post them somewhere, I think.

As it stands, I get about 90W out of the duplexer, which I think was right about the spec that Motorola said for repeater operations. I did notice that now the receiver seems to "hang open" so I think I'll go in and tighten up the squelch pots a tad and see if that helps. After I finish "making some dry runs" or "burning in" the machine, I'll drag it to the tower site and stick it on the air. And not too soon, either - my homebrew machine has developed hearing problems.
Mark - N9WYS
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kcbooboo
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by kcbooboo »

I bought 20 (minimum quantity) Xicor 9312UP chips to replace U831 on the six stations I got. I sold four more to someone else. I still have 10 of these guys. So far they're all working just fine.

I will sell them for $6 each, plus $2 s&h (padded envelope plus postage) for each order, if anyone still needs some. Contact me via PM for details. PayPal or USPS Money Order only.

Bob M.

All the chips are sold as of 22-Jan-09. I have no more.
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Mastertech
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Mastertech »

Hey N9W, I am using a set of wacom duplexers for which I made the cables. After extensive tuning and tweaking I get 104 watts out when I put 150 watts in. On the receive side, I can key the machine with .1 microvolts through the cans. Very little desense when I test it. In otherwords, sounds like your cans are working.

My machine is about ready to go up to the site; I plan to take it to Westchester NY on Friday. I ended up with a machine that I would describe as both good and bad. the PA's are only a few years old and the fan tray was new as well; overall the thing looked very petty (no scratches, no dings). However, I had to replace several IC's on the SSCB and a cap or two to get the TX audio to pass. In addition, the PURC HSO that i bought died (it was a moto part) so I had to buy another moto HSO, however, this one is solid. Moreover, I had the PO pot fail (replaced it, moto still has them) and found that the preselector whas horribly tuned. When I got the machine I had to inject over a MILIVOLT into it to ket it up! I can now key it from the IFR while injecting .075 +/- .05 microvolts directly into the SMA, its really very hot now. Finally, I found that the coax going from the uniboard to the IPA was damaged, so I had to replace that as well. Fheeewww........ that all sucked a lot!!! BUT.... BUT....

After all of this, however, I did infact survive this machine and the audio sounds beautiful. No hums, or weird noises, just a good solid and very quite carrier.

I think the machine will be on the air by the end of the month. The freqs are: (unless they need to change)

Input: 927.9875
Output: 902.9875
PL: 114.8

The antenna will be an Andrews with 6db gain.
Mastertech
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Mastertech »

Hey Bob, sounds like we have the same cans here. I will be putting mine in a speerate cabinet that will also house a bird meteing panel and a new station controler. Im doing this simply because there really just isn't that much room with the cans in the MSF cabinet; the door won't clear the phasing harness (RG393). I post photos when I have a chance.
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kcbooboo
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by kcbooboo »

I know that NOBODY on BatLabs ever reads stuff on other web sites, but there's two new MSF5000-related articles over on http://www.repeater-builder.com, in the Motorola area, MSF & PURC section. Both are based on these New Jersey 900 MHz repeaters; one covers adding a duplexer inside the cabinet.

Bob M.

[ toot - toot ]
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W6JK
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by W6JK »

Nice work, guys! I sure wish I could have a chance to play.

'JK
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w2ymm
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by w2ymm »

Hey Bob, I can't seem to keep up with all your articles.
Thanks for all the great information. :D I'm learning alot.
And you used one of my pictures :lol:
Bob P W2YMM
Robert Prybyzerski Jr
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ayaresr
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by ayaresr »

Maybe its me, but I'm having a hard time finding the connector for the hso power. There's a connector on the right side of the tray that looks close, but its already being used for the synth. board on that side of the tray as well. I haven't torn too deeply into this, as I was working in the corner of the garage with little room. Another project is now complete, so this can now move to the top of the to do pile. Not to mix too many issues at a time, but does anyone have suggestions for 900 MHz radios? I have been fighting with the band hack for the Spectra, looking for other ideas as well.

EDIT: Looking into it further, am I correct that I just need to splice power off of that connector on the right of the tray and use that...is this correct?
Thanks, Ryan
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rrfd43
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by rrfd43 »

I have GTX mobiles and portables in serice without anuy issues. Simple to set up and use. Not many options though. I also have 3 mtx9000 and like them alot but two do not lock when cold.

I have two converted spectras, I did not do them. They work well, but don't even have scan as an option.

I just got an MCS2000 model three works good on the bench, soon to go in the truck.
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by kcbooboo »

Re: HSO Power: that's basically what I did. I put my new Vectron HSO in the same chassis section as the reference synthesizer board, and soldered two wires to the power connector on the ref syn board to feed a low-dropout 12V regulator to power the HSO. I also replaced the 1A fuse under the right side of the tray with a 1.6A fuse, since the HSO draws just about 0.6A for the first three minutes.

I know nobody here ever reads stuff on Repeater-Builder, but perhaps you should go look over there in the MSF section; you might just increase your knowledge a bit.

Bob M.
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

Well, guys, today is the day! The MSF is going to the tower today for installation. I'm pretty sure I have all the bugs worked out, so the "acid test" begins at noon.

One thing I've noticed is that once I installed a duplexer (a TX-RX Model 28-88-0101) the receiver became desensed to a degree. In other words, I needed to increase the squelch settings of the repeater quite a bit to keep the receiver closed once the incoming signal dropped. I wish I had the option to use split antennas - I think the RX would perform much better. But it is what it is...

Now I'm beginning to wonder if this four-cavity duplexer I installed is giving me the isolation I need. (The spec sheet says 90dB.) I guess I'll find out once it gets on the air and operates for a while... what kind of incoming signal range I get. If I need to, I can swap out this duplexer with the set that is in my homebrew repeater (another TX-RX Unit, Model 26-88-01A -- three cavities and a combline; this one is showing 105dB isolation on freq) but that will require that I cut a hole in the front door of the MSF's cabinet to allow mounting, even if I can come up with some innovative installation scheme - something I'm not prepared to do yet. Oh well - this machine will still be better (I hope) than what I have in place now.

I'll keep everyone posted on how this all plays out.
Mark - N9WYS
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by ayaresr »

Anyone have suggestions for a good duplexer and possibly a good source? That's the last piece to my puzzle so that I can get this beast on the air.
Thanks, Ryan
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n9wys
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

ayaresr wrote:Anyone have suggestions for a good duplexer and possibly a good source? That's the last piece to my puzzle so that I can get this beast on the air.
Thanks, Ryan
I cast out a post on the Repeater-Builder list, and got a "nibble" from one of the list subscribers. Also, Jeff DePolo (also on that list - e-mail to: jd1@broadsci.com ) builds duplexers to spec. I bought one from him along with an isolator (a TX-RX Model 26-88-01A referenced in my earlier message) . I used it very satisfactorily in my homebrew 900 MHz repeater. In my opinion, his pricing was reasonable too.
Mark - N9WYS
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

A follow-up regarding my MSF5000 installation...

It's on-the-air as I write, and it appears to be working VERY satisfactorily!! I can work it with an HT from home -- about 17 miles as the crow flies, I'm using a GTX portable, and there are some terrain issues between here and there. I worked Jim (WA9FPT) on the machine from his mobile until I had to bail out of my car for a Physical Therapy appointment... he was about 25 miles away (using a Spectra at about 25W) and was still full quieting at the time. It'll be interesting to see what kind of range this thing has now! (The homebrew machine NEVER provided this kind of coverage...)

So, suffice it to say that I'm REALLY HAPPY right now!! 8)
Mark - N9WYS
Mastertech
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Mastertech »

The HSO power: ok the plug you saw next to the synth power uses an audio ground and was intended for the tx/rx relay. According to a friend a t MOTO who use to work on these machines at the moto depo they ran a wire up to the upper left hand large cap on the top power supply. This is how I hooked it up and I think it is a bit less invasive and perhaps more robust to go this route rather than to go off the synth board. No matter what however, do not use J15, the connector next to the synth power.
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

Well, Houston, I have a problem.

My machine has been on the air for almost a week now... Yesterday and today, I’ve had a chance to really give it a “shake down” and I’ve noticed an issue that bothers me. I’m not sure what is causing this, so I’m reaching out for suggestions/thoughts.

When I engage in a QSO on the machine for an extended period – like 10 minutes or more – I get an audio alarm right before the repeater drops. It is a double beep, ("beep-beep") and it happens after each transmission. However, if I allow the repeater to “rest” for even a short amount of time (like 1 minute or more) it “resets” – goes away.

I’m wondering if this is some sort of SWR alarm? The actual SWR read by my Bird at the antenna connection on the station shows ~125W forward and ~1W reflected. My feedline is approx. 50' (yes, only 50 feet) of 1/2" Heliax into a Decibel 6dB omni antenna. Could it be because I’m using the circulator originally installed in the machine – and obviously slightly detuned for the frequency it is currently operating on - or is there some other issue that may require my attention? Is anyone else experiencing this?

Any ideas?
Mark - N9WYS
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Doug
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Doug »

Marc,
Here's a link to the audio alarms generated within the msf

http://batboard.batlabs.com/viewtopic.p ... rms#p58529

I hate to say this but your going into a PA failure. This can happen because of several issues. SWR can be one of them but in this case it doesn't seem to be the issue. Another could be a thermal issue which is the way I'm leaning toward. I'm not real sure of what your PA is rated for. I have always used the 75% rule by that I mean say if you have a 100 watt pa I always run them at 75 watts before the duplexers. Maybe I'm fortunate in that running it at 75% of rated output I have not created any spurs looking at things with the spectrum analyzer. I am also a firm believer in cooling fans I usually do an over kill on this.
Hopefully this helps some
Doug
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n9wys
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

Doug wrote:Marc,
Here's a link to the audio alarms generated within the msf

http://batboard.batlabs.com/viewtopic.p ... rms#p58529

I hate to say this but your going into a PA failure. This can happen because of several issues. SWR can be one of them but in this case it doesn't seem to be the issue. Another could be a thermal issue which is the way I'm leaning toward. I'm not real sure of what your PA is rated for. I have always used the 75% rule by that I mean say if you have a 100 watt pa I always run them at 75 watts before the duplexers. Maybe I'm fortunate in that running it at 75% of rated output I have not created any spurs looking at things with the spectrum analyzer. I am also a firm believer in cooling fans I usually do an over kill on this.
Hopefully this helps some
Doug
Thanks for the link, Doug.

The station is equipped with fans - three of them - and all are working. In fact, I can feel the air blowing out the vents in the sides of the case, plus I made sure they were all working before I took the station to the tower site.

The station is rated 150W and is putting out approx. 125W - equal to about an 80% rating. (I know that's not 75%, but it is derated from max.) Maybe I need to bring it down a tad more... or maybe this one is getting ready for a PA failure. One of the other stations I brought home from NJ had PAs in it that had been rebuilt. The only thing that's strange is that the alarm only goes off after the station has been operating for a while, so I do wonder if the failure might be heat related. <sigh> Oh well... if it's not one thing, it's another, eh?
Mark - N9WYS
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by Doug »

<sigh> Oh well... if it's not one thing, it's another, eh?

I think we refer to it as character builders. If it were me I'd drop it down a tad more and see what happens...its possible that one of the stages in the amp is starting to get weak as well and everything else works harder to compensate for it creating more heat that usual as well. Have you by chance plugged into the pa and measured the stages if memeory serves they should all be within 5ua of each other



Just remember MSF's are our friends..??...
May the Schwarz be with you.
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n1oty »

Mark,

Send an email to Tony (NN1D). His MSF5000, which is working beautifully, exhibited this problem for awhile. I know he resolved this. IIRC, I believe it may have been an issue concerning the cabling at the duplexer, but I'm not sure. He has faced this problem and resolved it, so he is the one to talk to.

John
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n9wys
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

I have received some suggestions from the list here, as well as via Repeater-Builders. All good suggestions, so I will take them all into consideration the next time I venture to the tower site. Thanks everone!

No, I did not take current measurements on the PAs while I had it at the shack, because it did not malfunction here. Of course, it waited until it was installed before it decided to "act up." ARRRGH!!

Ah yes, a character builder for sure!!
Mark - N9WYS
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by fineshot1 »

Hey guys - I am not sure how its done(there is an adjustment procedure) but the PA alarms have a setable threshold. I beleive after the frequency is reprogramed these thresholds must be adjusted, and I think this adjustment procedure is in the manual. It may be as simple as either slightly backing off the power out or re-adjusting the pa alarm thresholds.
fineshot1
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

fineshot1 wrote:Hey guys - I am not sure how its done (there is an adjustment procedure) but the PA alarms have a setable threshold. I beleive after the frequency is reprogramed these thresholds must be adjusted, and I think this adjustment procedure is in the manual. It may be as simple as either slightly backing off the power out or re-adjusting the pa alarm thresholds.
OK - I'll have a lookie-see at the manuals. Thanks!
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Re: HSO FS Alert

Post by fineshot1 »

Those of you searching for an HSO may wish to pm this fella in this for sale thread below.

http://batboard.batlabs.com/viewtopic.php?f=2&t=77639
fineshot1
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n9wys »

I have two 10MHz HSO's and, for the right price, I might be convinced to let go of one of them... <wink>

If you set the jumpers correctly, they CAN be used in the MSF. (The reason I didn't use one of them in mine is that I'd bought a 5MHz unit from Alltronics before I came across these.) Details available upon request.

PM if interested.
Mark - N9WYS
n1oty
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Re: MSF5000 repeaters in 900mhz - any interest?

Post by n1oty »

We are planning another road trip to NJ for next Wednesday. Tony (NN1D) received a call this afternoon regarding the remaining MSF-5000's. They are scheduled to be scrapped late next week. We plan on picking some up next Wednesday at $50 a pop. This is the LAST chance for anyone wanting these fine repeaters. They have over 50 remaining, so there is more than enough for everyone. Anyone wanting in on this deal will have to be there on Wednesday.

John
N1OTY
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