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Anritsu MS2721B internal CF card missing

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brainstorm:
Hello @AnalogRF,

I now have a proper lab PSU that can do up to 30V and 6A (ITECH triple output IT6302)... it is definitely a big improvement over the dodgy chinese wall wart I had before XD

I have been chasing the voltage rails you mentioned under the Anritsu tin can:


--- Quote --- You must have the 12.2V (I think at two of them IIRC), 1.8V,3.3V, 5V, 4V
--- End quote ---

I have attached a few of them in this post, it would help a lot if you could verify that those are the same you are seeing on your board. I'm powering the main board with 15V and it barely consumes 350mA, no chip gets hot AFAICT and I've disconnected *everything* (no screen attached, no cold tube board, no CF card, etc...). Please let me know if there's any critical rail that I should specifically check, I have "The Signal Path" youtube video screenshot as a reference, but since that video is from the "A" model (attached below, image with red post-it stickers), there are a few differences.

There's a very small "PWR_FAIL" via that reads 3.3V... but since it's close to the battery charging circuit, I doubt it's an "overall" diagnostic for the instrument's power supply, but just a battery present/not present type of check?

@AnalogRF, I could not locate the 12.2V rail you suggested. The closest seems to be the input voltage (using 15V input via the barrel jack, with 0.2V voltage drop for the cable leads).

As I mentioned a while ago, the processor seems to be alive (3.3V and RDY/RESET signals) and the screen does flicker on boot, but doesn't get very far. When I connect the screen, it oscillates very slowly between 300 and 400mA, which suggests a bootloop.

I'll be taking a closer look at the RAM chips soon since I have some suspicion that one of them is not behaving exactly as the other does, but if anybody has other good troubleshooting suggestions, I'm all ears ;)

brainstorm:
The RAM seems to have addresses being latched on Ax pins (see attached pinout from the datasheet), but no data is coming in/out via DQx pins (the RAM ICs in this device are on the 16x pinout)... I'll check the SuperH4 CPU next...

brainstorm:
The processor RESET line is high and there's a constant 33,3MHz waveform on EXTAL pin, but it's seemingly struggling to boot since the RDY spits out a train of repeated waveforms, goes silent for a few seconds and repeats (see attached SuperH4-RDY.png).

analogRF:

--- Quote from: brainstorm on October 24, 2020, 05:50:36 am ---Hello @AnalogRF,

I now have a proper lab PSU that can do up to 30V and 6A (ITECH triple output IT6302)... it is definitely a big improvement over the dodgy chinese wall wart I had before XD

I have been chasing the voltage rails you mentioned under the Anritsu tin can:


--- Quote --- You must have the 12.2V (I think at two of them IIRC), 1.8V,3.3V, 5V, 4V
--- End quote ---

I have attached a few of them in this post, it would help a lot if you could verify that those are the same you are seeing on your board. I'm powering the main board with 15V and it barely consumes 350mA, no chip gets hot AFAICT and I've disconnected *everything* (no screen attached, no cold tube board, no CF card, etc...). Please let me know if there's any critical rail that I should specifically check, I have "The Signal Path" youtube video screenshot as a reference, but since that video is from the "A" model (attached below, image with red post-it stickers), there are a few differences.

There's a very small "PWR_FAIL" via that reads 3.3V... but since it's close to the battery charging circuit, I doubt it's an "overall" diagnostic for the instrument's power supply, but just a battery present/not present type of check?

@AnalogRF, I could not locate the 12.2V rail you suggested. The closest seems to be the input voltage (using 15V input via the barrel jack, with 0.2V voltage drop for the cable leads).

As I mentioned a while ago, the processor seems to be alive (3.3V and RDY/RESET signals) and the screen does flicker on boot, but doesn't get very far. When I connect the screen, it oscillates very slowly between 300 and 400mA, which suggests a bootloop.

I'll be taking a closer look at the RAM chips soon since I have some suspicion that one of them is not behaving exactly as the other does, but if anybody has other good troubleshooting suggestions, I'm all ears ;)

--- End quote ---

i dont have that spectrum analyzer anymore. I fixed it and everything worked perfectly before I sold it.
however, if you watch Shahriar's video about MS2721B (or perhaps MS2721A which has a similar power supply anyway) he will show the voltages
on the board briefly. But there are lots of them clearly marked on the main board and you dont need any reference. All of them are clearly marked
2 or 3 of them are outside the PSU section (1.8V and 24V and perhaps one more 3.3V)
all of them must be stable and there was no pulse or noise or ripple on any of them as I recall. However, 24V only comes on when the system is booted (24V is the supply for the RF deck)

Vsys is 12V as I recall, that's what I was referring to. it is clearly marked on the board.

analogRF:

--- Quote from: brainstorm on October 24, 2020, 05:50:36 am ---Hello @AnalogRF,

I now have a proper lab PSU that can do up to 30V and 6A (ITECH triple output IT6302)... it is definitely a big improvement over the dodgy chinese wall wart I had before XD

I have been chasing the voltage rails you mentioned under the Anritsu tin can:


--- Quote --- You must have the 12.2V (I think at two of them IIRC), 1.8V,3.3V, 5V, 4V
--- End quote ---

I have attached a few of them in this post, it would help a lot if you could verify that those are the same you are seeing on your board. I'm powering the main board with 15V and it barely consumes 350mA, no chip gets hot AFAICT and I've disconnected *everything* (no screen attached, no cold tube board, no CF card, etc...). Please let me know if there's any critical rail that I should specifically check, I have "The Signal Path" youtube video screenshot as a reference, but since that video is from the "A" model (attached below, image with red post-it stickers), there are a few differences.

There's a very small "PWR_FAIL" via that reads 3.3V... but since it's close to the battery charging circuit, I doubt it's an "overall" diagnostic for the instrument's power supply, but just a battery present/not present type of check?

@AnalogRF, I could not locate the 12.2V rail you suggested. The closest seems to be the input voltage (using 15V input via the barrel jack, with 0.2V voltage drop for the cable leads).

As I mentioned a while ago, the processor seems to be alive (3.3V and RDY/RESET signals) and the screen does flicker on boot, but doesn't get very far. When I connect the screen, it oscillates very slowly between 300 and 400mA, which suggests a bootloop.

I'll be taking a closer look at the RAM chips soon since I have some suspicion that one of them is not behaving exactly as the other does, but if anybody has other good troubleshooting suggestions, I'm all ears ;)

--- End quote ---

you are measuring the MSOFET switching signals in some of these pictures. Just measure the output of each converter (at the output capacitor or even better at test points that are clearly marked on the board with voltage values)

also that 535mV is definitely suspicious . Does not make sense
 

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