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IFR-1600 WITH PHASE LOCK PROBLEMS

This forum exists for the purposes for discussing service monitors (This includes but is not limited to Motorola, HP, Aeroflex, GD, etc). Additional topics allowed include test procedures, interpretation of test results, where to find information about specific tests, antenna VSWR, return loss testing, duplexer and filter alignment, etc.

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kh7y
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IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Mon May 05, 2014 7:07 pm

Just turned on my 1600 and it is not working, now does not pass phase lock tests. I would like to know if there are some tests that I can make before shipping back to the mainland as the cost is very high. Red LED are are on in the 3rd LO and 90 mhz gen modules. I have checked cables, they all look good. Any help appreciated.

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby Wowbagger » Tue May 06, 2014 3:34 am

Can you feed 10MHz into the external ref port, to eliminate the TCXO as a possible culprit?
This is my opinion, not Aeroflex's.

I WILL NOT give you proprietary information. I make too much money to jeopardize my job.

I AM NOT the Service department: You want official info, manuals, service info, parts, calibration, etc., contact Aeroflex directly, please.

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby jry » Tue May 06, 2014 2:17 pm

My guess is you have the 2nd LO 1Mhz out ( 10Mhz ref divide by 10 ) missing. Maybe a bad divider or buffer amp in that module

Check for the 1Mhz signal at the 3rd LO and or 90Mhz gen modules. The 1Mhz should be one of the SMB cables going into the top of the modules ( come from the divider output through a buffer )

SHould be able to pop the SMB's off one of the modules and look for strong 1Mhz signal with a scope probe to the center pin and ground. One of the cables should have it if the 2nd LO is working.

If it's there than check the frequency and make sure that is dead on strong 1Mhz

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Tue May 06, 2014 10:32 pm

I put about 0dbm of 10.000 at the port on the back of the unit, still no lock. The 10 mhz osc. is working just fine. I see on the 2nd LO that there are 5, 1 MHz outputs. Can I use one of these to see if the 1 Mhz signal is present and if it is at what level should it be I can measure with my power meter.

Also many thanks for the quick ideas, it is appreciated.

Aloha

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Tue May 06, 2014 10:57 pm

OK I checked all 5 one mhz outputs on the 2LO and they are strong and one frequency within a hz or so. Also checked the cable J20 from the 2LO to the 90 Mhz gen module J3 and 1 mhz is there and strong.

What next?

Aloha, Fred KH7Y

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Tue May 06, 2014 11:22 pm

I checked the 1 Mhz signal level going to the 90MHz gen module and there is about +5dbm, so there is plenty of signal. The frequency is 1.00000 so close as measured at the J2 cable 20 from the 2nd LO. Hope this helps you.

Aloha, Fred

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Thu May 08, 2014 9:56 am

8) :D Thanks for the information. I checked the frequency standard and it is working and has about +6 DBM output on 10.000 Mhz. I also used a external 10 mhz signal at the back of the 1600 however it made no difference.

I checked all 5, 1KHz outputs on the 2nd LO and there is 1.000 Mhz signal present, I checked cable going to J2 and J3 on the 90 mhz gen and 3rd lo plenty of 1.000 mhz sisgnal present. Still PLL lock problems with the unit.

Where do I look next?

Again I really appreciate the help!

Aloha, Fred

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby d119 » Thu May 08, 2014 4:34 pm

Dumb question - did you reseat all the PCB's in the thing?

Mine did the exact same thing last week, I took the lid off to find that somehow, one of the cards had worked its way loose.

I was getting "F" on the PLL self test, and the frequencies were displaying in yellow. Scared the crap out of me as I'd recently purchased this thing, and it has under 375 hours on the counter!

Pushed it back in, and it's back to normal.

Any chance that happened to you?

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Thu May 08, 2014 5:30 pm

Yes I checked all the PCBs before I asked for help... I have looking into the 2nd lo and there are two 1210 MHz outputs one has 2 buffer amps but the output is only a few DBM stronger J11 is - 2 DBM and J7 is -3 DBM both outputs are moving around +/- 6dbm on my HP power meter.

I will pull all the PCBs again just in case.

Thanks for the input, Aloha, Fred

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby jry » Fri May 09, 2014 5:29 am

1. Remove A22 RF I/O (para. 2-2-4) and install on PC Board Assembly Extender in Test Set.
2. Run Self Test 15 in Extended Mode until failure is detected.
3. Verify voltage for failed test with DMM at A22P2 (Figure C-22).
Failed Test Location Voltage If incorrect, perform
15.1 A22P2, Pin 11 B 5 Vdc (±O.S Vdc) Step 4
15.2 A22P2, Pin 2C 5 Vdc (±0.5 Vdc) Step 5
15.3 A22P2, Pin 3C 5 Vdc (±0.5 Vdc) Step 6
15.4 A22P2, Pin 12C 5 Vdc (±0.5 Vdc) Step 7
15.5 A22P2, Pin 14C <0.4 Vdc Step 8
• If correct, replace A22 RF I/O (para. 2-2-4).4. Disconnect W20 (Figure C-2) from A9 90 MHz Generator (Figure C-2), connect Frequency
Counter to W20 (Figure C-2) and verify 1 MHz (±0.5 Hz).
• If incorrect, perform Step 9.
• If correct, replace A9 90 MHz Generator (para. 2-2-4).
5. Disconnect W14 (Figure C-2) from A 10 1st La (Figure C-2), connect Frequency Counter to
W14 (Figure C-2) and verify 10 MHz (±5 Hz).
• If incorrect, perform Step 9.
• If correct, perform Step 10.
6. Disconnect W15 (Figure C-2) from A10 1st La (Figure C-2), connect Frequency Counter to
W15 (Figure C-2) and verify 10 MHz (±5 Hz).
• If incorrect, perform Step 9.
• If correct, perform Step 10.
7. Disconnect W19 (Figure C-2) from A7 3rd La (Figure C-2), connect Frequency Counter to
W19 (Figure C-2) and verify 1 MHz (±0.5 Hz).
• If incorrect, perform Step 9.
• If correct, replace A7 3rd La (para. 2-2-4).
8. Disconnect W18 (Figure C-2) from A5 Analyzer RF (Figure C-2), connect Frequency Counter
to W18 (Figure C-2) and verify 1 MHz (±0.5 Hz).
• If incorrect, perform Step 9.
• If correct, replace A5 Analyzer RF (para. 2-2-4).

you can just tack a wire onto the PCB o measure the point without an extender. The connector referenced is one of the motherboard connectors and I think the PCB is labeled.

This is the first part of that self test failure trouble shooting that covers the RF i/O card for the main self test you have failing. Some of the follow-on steps you have done but not all.

The 1210Mhz outputs should be stable if the 5vdc and 15vdc are good ...should be some decent levels on both and fixed. Would have to check the manual for the exact values but doubt that is the core issue since the 90Mhz is not locking.

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Fri May 09, 2014 10:01 pm

Hello and thanks for the step by step instructions. I have the maintenance manual which says with illustrated parts catalog. However all that part is missing or I need another manual. I have no diagrams of the circuit cards at this point. I did the expanded test 15 and this is what is shown. 90 meg gen fail, 1st Lo gen pass, 1st lo receiver Pass, 3rd LO rec fail,
Analyzer pass. Does any of this point to the problem?

I will see if I can pruchase a complete maintenance manual with diagrams and parts layout to do further testing.

I checked the 1210 MHz levels of to the 2nd LO and the levels vary 6 to 8 DBM. At 11 -2dbm and 7 -3dbm as shown on page 2-51. The levels are moving all over the place on both outputs.

Your time and input is appreciated, Aloha, Fred

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Fri May 09, 2014 11:10 pm

Also on my PCB there are no numbers which makes it tough to measure anything. There are no diagrams in my manual either. I need to find some.

Thanks again for your time. Fred

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Sat May 10, 2014 11:21 pm

I understand about the 90Mhz unit. My problem is that there are no numbers on that module and looking at the connectors I see no numbers on them either. I do not have the extender card, I will see if I can find one and purchase or borrow till we get my unit working. My original manuals do not have any diagrams or pictorials of the circuit cards. All I have are block diagrams. The numbers like 3.3 I cannot find any reference about them in my "illustrated parts calalog. There is not even a parts list other than the modules in section 6 and 7. So if there is a place to purchase the circuit diagrams, parts lists, and circuit board layout I sure would like to get my hands on them. Nothing on Ebay today. I also will look at the Dayton Hamvention next week also


I will wait for your next reply.


Many thanks, Fred KH7Y

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Sun May 11, 2014 12:45 am

Here is a update I had stated that the 1210 Mhz signal at J10 on W11 was not stable, the fact is it is stable also W7 is stable. Something in my test cable was messed up. Also the level at J10 is -9 DBM and J9 is +5 DBM.

Next I preformed all tests A22 I/O 4 through step 8 all frequencies are present on the cables you listed

I cannot do much on the voltages on steps 1,2,3 till I get a pin out or diagram for the RF I/O module

Again the expanded PLL tests are:
90 meg gen FAIL
1st LO Gen Pass
1st LO rec Fail
Analyser Pass

I wanted to make sure I did not send U a curve ball with the 1210 MHz signals etc.

Thanks, Fred

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby jry » Mon May 12, 2014 9:27 am

you may have multiple issues or a bad RF I/O board ?

the 1st LO gen passes but the 1st lo rec fails. ...the only difference is the buffered ref signal going in and the data programming between those two ...identical circuits otherwise.
One would assume the buffered reference is good but you could swap between the two ports just to verify or measure.

The 90 Mhz gen fails ... you verified the 1Mhz reference so it may be bad programming data or another failure on that card ...have not really looked that close at the manual for the RF I/O or 90 Mhz Gen.

May be an issue on the RF i/O causing the multiple failures since the references looked good.

Believe there was a difference in the 1210Mhz output levels going from memory. Either way that should either cause either poor RX or a Power Meter failure ( needs the correct sig gen out level to test the ) power meter and it looks like you may not be making it that far for those type of tests to be valid anyway.

Easy way to troubleshoot this would be to swap the RF I/O module and go from there.

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Mon May 12, 2014 9:54 am

Sounds like we are getting real close the the problem. I will swap ports and see if the fail 1st lo RX remains.

Now for the big question, I have looked on Ebay for 1600 parts, without any luck. Lots of 500 and 1200 parts zero 1600. Do you know if there is a company or person that sells rebuilt or tested modules?

I am going to Dayton later this week and will keep my eyes open also there.

Thanks again for you time.

Aloha, Fred

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Mon May 12, 2014 11:59 am

Another update

I replaced the jumper from 1st lo Rec as the original one was intermittant. expanded PLL test now

90Meg gen Fail
1st LO Gen Pass
1st LO Rec Pass
3rd LO Rec Fail
Analyzer Pass

I will be looking for any info on a replacement board or a company that can repair my existing RF IO board

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Mon May 12, 2014 11:09 pm

I found out that Areoflex will repair the module, So will call them in the morning and ship it off for repair. Once back will check in here.

Thanks again for your time helping me.

Aloha, Fred KH7Y

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Sat May 24, 2014 2:43 pm

UP date, I sent my RF/IO board to a friend with a working 1600. He installed my board and it works just fine, there are no errors etc. I am looking for more instructions from this information about the RF/IO module being OK.

Aloha, Fred

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby jry » Tue May 27, 2014 2:35 pm

May be good to understand the current issues since it sounds like you may have fixed one of the problems.

Which main self-test is failing first and what are the current extended test results ?

If you have not done so already verify the power supply levels and re-seat the PCB's and verify the RF connections are tight/ seated.

You may have done some of this already

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Tue May 27, 2014 9:08 pm

Hi, the first to fail is the 90 Meg gen. I am going through all the coax jumpers and making sure they are in good shape. I sent the 90 meg gen and 3rd lo to my friend in TX to install in his 1600. I do have the service manual printed for the government. It does has much more information and voltages. So maybe the 90 meg gen has a problem. I should know by this weekend. I will post here. Until will continue testing cables. This problem started after being shipped. Worked well before and not after arrival.

Thanks again for your time all input appreciated.

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Tue May 27, 2014 9:12 pm

Didn't answer all your question correctly. The first to fail is the PLL then expanded is 90 meg gen. Voltages from the power supply are fine. I have pulled every module and reseated. I am checking all jumper cables now, also connectors and soldering on the modules just in case.

Again tnx.

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby kh7y » Mon Jun 02, 2014 11:29 pm

Turned out that both the 90 gen and 3LO were bad when checked in another 1600S. What was found were shorted tantalum capacitors and RF chokes in both modules. They are both working now in my friends 1600. Should have them back later this week and see if my 1600 comes back to life.

Thanks again, Fred

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby d119 » Sun Aug 31, 2014 4:15 pm

Fred - did it work??!

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby Dan Gibbs » Fri Apr 01, 2016 5:48 pm

Hey all :)
I'm having a problem similar to Fred KH7Y above in this thread. My problem is that my 3rd LO unlocks shortly after I power my 1600S on - between 30-seconds and five minutes. It depends on how warmed-up the 1600S is.

I've confirmed that it is a thermal issue in the module. In my last testing this evening at work after hours, I removed the shields and case, placed the module in the freezer for about three minutes, reinstalled and got the longest run-before-unlock yet since this problem started a few months back at work.

My 1600S worked fine from August 2013 until about December of 2015 under my very limited usage at home and work (WEYI-TV25) since I received it. Of course age is catching up with it too, so it's time to try to fix it.

I've used my Fluke 79 to do short-checks on the tantalum caps in the 3rd L.O. module - none were burnt and none are shorted yet. I'm thinking that maybe my next move is to replace the original tant-caps with some Panasonic FC-series electrolytic caps that I have on hand - perhaps one of the tant-caps is getting close to shorting?

Another simple try for me is to reflow the solder joints for the components on the PCB as the next step.

At that point, I will need a schematic for this module and preferably a component location diagram also. Neither of these are in the maintenance manual that I have from online. Can anyone help and provide this schematic?

I personally bought this 1600S to help repair my other FM/AM-1500 within which the output amplifier smoked due to failing tantalum caps. I have that working again short of the GEN function because I can't fully repair the output-amp due to lack of equipment and RF adapter cables on my own or at my workplace (TV station). (I still love my old 1500 a lot and want to get it up again too).

The "once I fix this" next issue is the dead backup battery(ies) problem - that's a whole other issue once I get the 3rd LO back up and fine.

Please help!!!
Dan G.
KD8SSS & bench tech

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby jry » Sun Apr 03, 2016 7:25 am

1. verify that it is the 3rd LO by running the Self test "LOCK TEST" in extend mode ...I assume the LED on the top is coming on though.
2. If you have the can off look down on the board when it fails and see which LED's are on.

There are actually three loops on this board and this assembly tend to fail for numerous reasons ...if all three are lit you may be lucky and just have a bad connection on one of the power chokes.

If it's just one then you may have an alignment /component drift.

There are no schematics released that I have ever seen on most 1600 modules ...you just have to reverse engineer based on the block diagram and parts used.

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby Dan Gibbs » Sun Apr 03, 2016 12:41 pm

Hello JRY
I ran the 3rd LO loop test three times last Friday for a about 4-5 minutes each time...it always failed. As I said in the last post, if I put the 3rd LO module in the small shop refrigerator for about 4-5 minutes and cool it down, it will work fine until the board warms/heats up again and unlocks.

You mentioned LED's on the component-side of the PCB....I think there are three that I see. I will try to peer in and see which ones light up, or I'll make a 20-pin extender cable so that I can easily see them with the card out of the slot.

Also, there are two male MCX (?) connectors on the PCB in the middle...any idea what signals are there?

I was going to embed a picture of my PCB here but I'm not sure how to accomplish that. Here a link to the pic on Flickr. What I think are the LEDs are circled in yellow. The two MCX males are circled in green.

https://www.flickr.com/photos/49770894@ ... ed-public/

My 1600S is at work so I won't be able to try anything until tomorrow.

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby Dan Gibbs » Mon Apr 04, 2016 4:55 pm

Okay, I got to test the board today, but only safely in it's slot with it's outer shield and top-shield removed. Turn the 1600S on, 3rd LO top unlock LED and the three small board LEDs all lit up for about 10 seconds and then all went off. After about 30 seconds, the top unlock LED lit back up and only the bottom right LED on the board lit up. The upper left LED and the lower middle LEDs both stayed unlit.

Does anyone know which LED corresponds to which part of the block diagram? I'm kinda hosed for any further testing at this point as I need three SMB extender cables and a 20-pin 0.1-pitch extension cable for the PCB itself to get the card OUT of the mounting slot to be able to test any further.

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby Dan Gibbs » Tue Apr 12, 2016 5:13 pm

Well, I'm a bit scared to say anything, Murphy's Law and all, but I made a bit of progress at work after hours tonight. After hooking up the SMB extension cables that I bought and 20-pin backplane extension cable that I made, I was able to power up the board outside of the chassis - guess what...absolutely no lock at all. The top LED was on as well as the lower right internal LED on the board. Damn. I removed the SMB jumpers and 20-pin extension cable to see if they were the problem - plugged the board back into the slot and repowered - solid-on unlock LED and lower right internal LED. Damn-damnit!

So I finally started inspecting the board closer and noticed a solder-joint on a collector-pin on a sot-23 smt transistor in the middle-right quadrant looked a bit "poorly" from the factory. I touched it up and decided to touch-up the pins on most of the smt transistors and smt IC's on the board. Popped the board without the shield cover on it back into the slot and fired it up again. Unlock LED went out after about 5-7 seconds and STAYED OFF!!! It burbled a bit just before it turned off, but it STAYED OFF! After running well for about 45 minutes, the radio station I was tuned to went to static. I twisted the operating board in the socket CW a little bit and the unlock LED went off again! I then put a couple of folded paper-wedges to hold the twist at a working angle and it worked for another 45 minutes.

I then put the top outer case-cover back on and boxed it up as ready for sale on eBay.......NO NO NO...just kidding. I'm letting it run overnight on my workbench and hoping that it's still working in the morning. If so, then it's a bit more solder touch-up and hopefully good. If not, possibly a cracked smt resistor or smt capacitor or such to find and fix.

Crossed fingers and high hopes for now,
Dan Gibbs :)

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby zs3cd » Thu Aug 18, 2016 10:43 am

Hello Friends name is Mechiel. Having same problem with my IFR1600S. Crying myself to sleep and even worse stuck in south Africa help around here is going to be absolute. Please any help and direction would be helpful. So far: Self test menu15 extend 90mhz gen -ok /1st lo gen -ok /1st lo rec -ok/3rd lo rec -fails/Analyzer -ok. Menu 16,17,18,19,20,21,22,23 -fails. The machine works fine sofar I only see that the rf attenuator is about 40db low.
Thanks.

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Re: IFR-1600 WITH PHASE LOCK PROBLEMS

Postby jry » Mon Aug 22, 2016 7:50 am

you may be better off starting a new thread with a specific issue since it sounds like you do not have a problem with any of the loops locking.

Start with the first failing test and extend that to see what details you have. You have to have some other test equipment to even reasonably attempt to service these units.

The variable output attenuators do often fail.

Easy check is to make sure you have 0 ohms resistance through the variable attenuator. If not that's one problem and the attenuator needs to be replaced.


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