Repair of Anritsu S332D - Page 1
Forum section: electronics / repair

author: m0vse
author_rank: Contributor
timestamp: March 01, 2019, 01:13:31 pm
content: Hi all.I have an Anritsu SiteMaster S332D that had been in the wars!After replacing the cracked screen and missing battery, it also fails the self test with "Integrator Failed" error which has me stuck.I contacted Anritsu and they wanted lots of money (many £100s) just to look at it so I politely declined.Does anybody have any experience with these and can give me some pointers where I could look? The spectrum Analyser function seems to work OK but I was really hoping to use it for testing a 2.4ghz patch antenna.edit: I realise this probably means that somebody has injected high RF into the device at some point!ThanksPhil Taylor

author: metrologist
author_rank: Super Contributor
timestamp: March 01, 2019, 09:53:54 pm
content: I will help you.Can you open the case and take a picture of the area where the input coax terminates to the PCB? Also, if you can follow the incident path to the first stage amp and tell me the chip marking.

author: m0vse
author_rank: Contributor
timestamp: March 02, 2019, 09:41:25 am
content: Great, thanks for your reply. The RF input enters the main PCB underneath a large metal can which covers both the front and back of the PCB. I have removed the can and this is what was beneath it (from both sides).Phil

author: m0vse
author_rank: Contributor
timestamp: March 02, 2019, 09:53:29 am
content: The previous pictures are of the RF output section (marked RF Out / Reflection on the socket). As the spectrum analyzer part of the unit seems to work OK I thought that the input was OK? What do you think.I have removed the (gold coloured) can from the input section and a pic of this is attached.ThanksPhil

author: metrologist
author_rank: Super Contributor
timestamp: March 04, 2019, 07:04:58 pm
content: What is the main board number and rev? They look a bit different. The spa board should be fine.Usually when these are overpowered, like plugging into a powered cell station, the area below the ferrite beads is charred. I did not see signs of burning there. The amp was sensitive to static - so that could get zapped when connecting an antenna.

author: m0vse
author_rank: Contributor
timestamp: March 04, 2019, 09:24:25 pm
content: Thanks, I will check those and report back.The mainboard is 64968-3 Rev E_/APhil

author: metrologist
author_rank: Super Contributor
timestamp: March 04, 2019, 09:57:55 pm
content: If you want to probe the RF path, you can set CW mode...

author: m0vse
author_rank: Contributor
timestamp: March 04, 2019, 10:50:31 pm
content: I get nothing when trying any of the sweeps, they run very slowly and nothing registers on the display.I have a 1Ghz spectrum analyzer that if I connect it to the n-type socket, I can see the signal sweeping up (slowly) so it is obviously generating something?It looks like the component numbering is different to what you are quoting as other than TP13 (marked INC_IF) I have different numbers for everything!What would I expect to see at TP13?Thanks again for your help!Phil

author: metrologist
author_rank: Super Contributor
timestamp: March 05, 2019, 05:28:02 am
content: Incident IF. You should also find the REFL_IF. I think it might be easier to look at that if you set Meas to Fixed CW and then set F1=F2 (I think that changes it from FDR to TDR). You can check the amps and diodes along those RF paths.

author: m0vse
author_rank: Contributor
timestamp: March 05, 2019, 11:44:32 pm
content: Hi.When in Fixed CW, at both test points TP13 (INC_IC) and TP14 (REFL), I can't see any significant RF at the frequency that I have set (50Mhz). I can see quite a strong 50Mhz signal on the output.I have started to trace the circuit around the RF IN/OUT in an attempt to understand how it works but many of the components have quite obscure markings that I can't find!SW1 which is marked S218/4895/529 is one and also U70, just below both TP13 and TP14 is marked just D/OQ (it is a 10pin SOIC) with connections to both test points. It is above U7 and U124 which are both AD8042AR and U24 which is an LTC1562.There is also U109 which is labelled H187/8699 and another which just says A5RAD on the top.Any pointers on the above would be greatly appreciated!Phil

author: m0vse
author_rank: Contributor
timestamp: March 06, 2019, 12:08:35 am
content: After a bit more "probing around", it looks like the MCL25 may not be working. I can measure 50Mhz on the input pin (3) but there is nothing on the output pin (6)

author: metrologist
author_rank: Super Contributor
timestamp: March 06, 2019, 01:39:24 am
content: I assume you see your signal on the semi rigid soldered to the PCB on both sides of the bead. What do you see on that blue cap to the right of SW1 in your pic? That looks like it goes off to the upper right. I see a duplicate circuit on the other side of the PCB.

author: m0vse
author_rank: Contributor
timestamp: March 06, 2019, 08:44:54 am
content: Yes I can see it on the semi-rigid and the blue component (which I think is a 50r resistor) and the cathode of the pin diode (PM2) and all the way over to the NPN transistor (C2T)Phil

author: metrologist
author_rank: Super Contributor
timestamp: March 06, 2019, 02:03:25 pm
content: You should see signal on TP29, which I see in your second photo. There should be a couple transistors in each path before the LTC1562 that you mentioned.

author: m0vse
author_rank: Contributor
timestamp: March 07, 2019, 12:45:22 am
content: Yes I can see the signal at TP29. Do you think it is worth replacing the chip marked MCL25? (it is a Mini Circuits VNA-25+ I think). I can see it is getting a bias voltage of 3.3v but there is definitely no signal at the output.Phil

author: metrologist
author_rank: Super Contributor
timestamp: March 07, 2019, 02:30:35 am
content: That part is rated up to 2.5 GHz. The signal path should accommodate the frequency range of the instrument. I think if you are looking at low frequency you are not down converting your IF.Can you post a picture of the board area or trace the signal path to the next component from TP29.

author: m0vse
author_rank: Contributor
timestamp: March 07, 2019, 08:43:49 am
content: Here is the same area from both sides, it isn't immediately clear (to me) where the signal goes so I thought I would post both!

author: m0vse
author_rank: Contributor
timestamp: March 07, 2019, 09:02:04 am
content: The picture of the rear of TP29 isn't that clear so here is another one which is hopefully a bit better!

author: metrologist
author_rank: Super Contributor
timestamp: March 07, 2019, 03:00:17 pm
content: It looks like in the first new pic, it goes to the left and there is something under the black coax. Not sure if that is coming or going there, but you should be able to find the next component using a continuity test. It is probably the next active component in the path that got zapped by static or something.

author: m0vse
author_rank: Contributor
timestamp: March 08, 2019, 02:38:03 pm
content: Yes TP29 is fed from a transistor which (according to the markings) looks like a BCW68GR. In-circuit testing was inconclusive so I have ordered some replacements from Farnell. The next active component looks to be a MMBT5087 so I have ordered some of those as well.ThanksPhil

author: m0vse
author_rank: Contributor
timestamp: March 19, 2019, 07:57:26 pm
content: Sorry not had much time to look at this for the last few days. I have tried replacing a couple of the active components but no joy yet!Phil

author: metrologist
author_rank: Super Contributor
timestamp: March 19, 2019, 08:44:09 pm
content: To recap, do you see signal at TP29? What signals do you see on the transistor at VT1 and the one on the way there?

author: R4PBE
author_rank: Newbie
timestamp: June 10, 2019, 08:02:46 am
content: Заменил VNA25, но безрезультатно, так же ошибка.

author: Pattymorr
author_rank: Newbie
timestamp: September 03, 2019, 04:50:44 pm
content: S332C with PLL error.Unable to find schematic somewhere or a guide for the PLL circuitry pathPictures under coaxial TP23 : I_ERR, TP46 : 12 , TP42 : +2.5A (which is actually 2.5V reference)Seems like the VCO is the square can on second picture top left surrounded on left by RF switches MSWT-4 -20 and on topt by 2 PLL Ic's LMX2320. The reference on shiny box is Z-Com V585ME30. None of the PLL had a valid signal on the Xtal input. There is a main LMX2330 PLL with a 6Mhz Xtal Colpttis configuration single transistor on pin 1 which was unable to oscillate. Found a resistor 511R to ground open as part of a voltage divider going to the PLL; conveniently, the resistor turns it self in to a 10pf Capacitor which was enough to attenuate all the oscillation. Replaced the resistor and a factory reset gave the instrument a Pass on the self test.Patty

author: vishaldotgupta
author_rank: Regular Contributor
timestamp: October 01, 2020, 05:40:23 pm
content: hiI have been repairing similar equipment on component level. you need to start step by step.1. Is RF available on Test port. if not or low level, mostly you get message integrator failed. check voltages on MMIC. also check for different bad RF Switches.2. if available, please make the equipment run on zero span on different frequencies to check on spectrum on freq value and level. If the freq is not correct, problem is with VCO, PLL tuning voltages, check for mosfets around VCO, OP amps for tuning voltages3. basically the equipment mixes the generated RF to generated two separate paths of around 400 KHz. One is called reference, other is measured or rfl value. if the equipment still doesn't sweep, check for reference path for mixer, Active RC filter (from linear), op amps of AD, and finally to A/D converter from Maxim / ADyou would also like to check voltages on A/D converter.hope this was helpfulmy experience says mostly, RF Switches, MMIC, Mixer, MOSFET switches, etc gets faultyTrust this was helpful

author: vishaldotgupta
author_rank: Regular Contributor
timestamp: October 01, 2020, 05:43:04 pm
content: please check with DMM that tuning voltage on VCO varies as equipment sweeps.if not check around PLL IC for clock, voltages, charge pump, and associated driver circuit which mostly consists of OPAMPS like LT1078

author: jasony_ng
author_rank: Newbie
timestamp: December 15, 2021, 04:35:14 am
content: hey, guys, I had successfully repaired my S331C by replace the E3 mmic amplifier for "integrator failed", and some 50ohm chip resistors on input port.I looks your photos, I think it should be on the place as my red circle marked.

author: rainbow
author_rank: Contributor
timestamp: March 16, 2022, 03:28:41 pm
content: Sorry if I add a little different model S331B to the discussion but this thread seems covering the S331/S332 lines.My device pass all self tests (from the menu and from the booting) but the sweep is very very slow and at each step the "Integrator Failure" icon appears. I think that the problem is in the latest stage near the output connector since it is not verified by "self tests" and the slow sweep is because it is waiting the return signal. What do you think? Someone has already encountered this problem?thank youps. In attachment the photos of the RF input.

author: rainbow
author_rank: Contributor
timestamp: March 17, 2022, 10:53:55 am
content: I did a few more tests to try to split the problem:- the "integrator failure" icon is more present if the frequency is lower than 900MHz- after ~1700MHz the instrument seems to work correctly and "integration failure" is very rare- at low frequency the signal in CW mode is intermittent- the output signal from N port has low power at low frequency (see images from spectrum analyzer) when in CW mode. How much should be the signal power in CW mode when the instrument is working?With an active probe and the spectrum analyzer I measured the following test point (I don't know if they are the same of the other boards)- TP40: -41 dBm CW signal- TP29: -50 dBm CW signal- TP19: -52 dBm CW signal and 8V DC- TP14: -52 dBm CW signal- TP13: a lot of noise without any preponderant signalI measured the white "Bc" component that I suspect is a two/three ways PIN diode (ports are numbered A, B and C from the top clockwise)STATIC:- diode 0.7Vf from A to B with 8M resistance- diode 0.7Vf from A to C with 64K resistance- diode 0.9Vv from C to B with 8M resistanceDYNAMIC:- each port show low frequency square wave (it is probably the switching DC signal but I haven't superimposed two ports)- port A 2Vpp square wave the other ports has 100Vpp

author: jasony_ng
author_rank: Newbie
timestamp: June 18, 2022, 08:51:25 am
content: Here is the S331C RF output on CW mode, it value around 0~-5dbm

author: vishaldotgupta
author_rank: Regular Contributor
timestamp: September 14, 2022, 07:26:24 am
content: integrator fail and slow sweep is generally due to faulty RF Switch, Attenuator or amplfiier.to verify connect a spectrum to the output and put the equipment in zero span and check the level of signal on spcectrum.ideally it should be close to -10dBm. if it is missing then amplifier is faulty. if lower by say 20dB, then attunuator or rf switch is faulty.if the singal is there but at some other frequency probably issues are there with PLL , reference clock, VCO etcanritsu uses different versions of boards for same model, some of them may or may not have switch or attenuator etcswi in picture is the switch. amplfiers are under the metal lidhope this helps

author: rainbow
author_rank: Contributor
timestamp: October 02, 2022, 09:27:08 am
content: Thanks to everyone for the support. Seems that the last MMIC (mini-circuits ERA-3) is faulty. Now I order a replacement and I will check if the values are correct.

author: Boofrmb
author_rank: Newbie
timestamp: November 06, 2023, 05:47:48 am
content: Hi All.Hoping someone may be able to help me get my S331A back up and running.All appears ok, but when I start the machine up, I have to adjust the contrast everytime, and then I get a "PLL fail" during the self test.Any ideas where to stay would be great, or even where I maybe able to obtain a cct.Thanks in advance.Robert

author: Boofrmb
author_rank: Newbie
timestamp: November 12, 2023, 02:34:08 am
content: Have added this section of the S331A, PLL section

author: Boofrmb
author_rank: Newbie
timestamp: November 12, 2023, 02:35:37 am
content: Complete S331A board.

author: Boofrmb
author_rank: Newbie
timestamp: November 12, 2023, 11:05:13 pm
content: Here is the board

author: 1VOX
author_rank: Newbie
timestamp: June 02, 2025, 08:05:34 am
content: Hello,I have S331D with intefrator failed. PCB board is different than S331C. Please do you know anybody S331D?

author: vishaldotgupta
author_rank: Regular Contributor
timestamp: June 04, 2025, 03:57:01 pm
content: mostly likely you have faulty mmic or Rf Attenuator or RF switchif you have another site master, try to measure the vswr of input connector of faulty site masterput site master in zero span model and say at frequency of 1Ghz, check on spectrum if you have a signal around -10dBmopen the second sheild and share pics

author: 1VOX
author_rank: Newbie
timestamp: June 04, 2025, 08:18:14 pm
content: File with pictures

author: 1VOX
author_rank: Newbie
timestamp: June 25, 2025, 06:05:24 pm
content: :palm:we changed 3 Mic, now is ok