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| HP 3458A - Fails Slave Test - Convergence |
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| Dr. Frank:
--- Quote from: Ade911 on July 06, 2023, 04:08:30 pm --- Hello Frank, No input, activating the Reset on the front panel All inputs now checked, On all devices you listed pin 1 gives 2 10us pulses from 0V to 4V, Pin 2 shows data stream, Pin 3 I cant read the clock maybe too fast for my old scope so sits high [+5v] and pin 15 is high [+5v] , started to try and test outputs which is difficult to achieve. Maybe its not a problem, A1 U10C, Im checking data coming from A1 U17 to the DAC but I dont see a W/R signal. U10 Pin 9 is connected to all devices just checked - PIN 1, I see 2 10us pulses as before , Pin 10 is sitting at 2V , the output A1 U10 Pin 15 just sits high even when Pin 9 goes above the 2V threshold , is this normal , I though being a comparator it would flip and drive to 0V. Anyhow Ill carry on checking the other outputs where I can of the devices you mentioned. Many thanks --- End quote --- Hi Ade, what kind of old scope do you have? Should be at least 20MHz BW, hopefully. The SR data might be clocked with 10MHz; I don't find the clock generator, or there should be a Hi speed UART on the analog side, which complements the UART A5U700, restoring clock and data, somehow. Well, that's the GA_Chip, A5U210, which serializes the data and creates all necessary signals for the different SR chains. It's clocked with 20MHz, so you should use a scope which has 60MHz Bw at least. This clock should be visible on all SR clock, and U10C serves as a simple inverter, delivering inverted clock for the DAC. Btw. there are ten SR '4094 in series on A1, in the following order: U1, U106, U307, U4, U14, U17, U6, U9, U201, U203. Check U203, pin 9, which is SERIAL OUT for the whole chain. If the clock signal is not present at all, and no data out at the last SR, then we might have found the problem. Frank |
| Ade911:
--- Quote from: Dr. Frank on July 07, 2023, 10:34:34 pm --- --- Quote from: Ade911 on July 06, 2023, 04:08:30 pm --- Hello Frank, No input, activating the Reset on the front panel All inputs now checked, On all devices you listed pin 1 gives 2 10us pulses from 0V to 4V, Pin 2 shows data stream, Pin 3 I cant read the clock maybe too fast for my old scope so sits high [+5v] and pin 15 is high [+5v] , started to try and test outputs which is difficult to achieve. Maybe its not a problem, A1 U10C, Im checking data coming from A1 U17 to the DAC but I dont see a W/R signal. U10 Pin 9 is connected to all devices just checked - PIN 1, I see 2 10us pulses as before , Pin 10 is sitting at 2V , the output A1 U10 Pin 15 just sits high even when Pin 9 goes above the 2V threshold , is this normal , I though being a comparator it would flip and drive to 0V. Anyhow Ill carry on checking the other outputs where I can of the devices you mentioned. Many thanks --- End quote --- Hi Ade, what kind of old scope do you have? Should be at least 20MHz BW, hopefully. The SR data might be clocked with 10MHz; I don't find the clock generator, or there should be a Hi speed UART on the analog side, which complements the UART A5U700, restoring clock and data, somehow. Well, that's the GA_Chip, A5U210, which serializes the data and creates all necessary signals for the different SR chains. It's clocked with 20MHz, so you should use a scope which has 60MHz Bw at least. This clock should be visible on all SR clock, and U10C serves as a simple inverter, delivering inverted clock for the DAC. Btw. there are ten SR '4094 in series on A1, in the following order: U1, U106, U307, U4, U14, U17, U6, U9, U201, U203. Check U203, pin 9, which is SERIAL OUT for the whole chain. If the clock signal is not present at all, and no data out at the last SR, then we might have found the problem. Frank --- End quote --- Hi Frank, Yes the clock is missing from U210 Pin 31, i traced and checked each signal back to the rear of U210 through R270,1,2 and the signal is missing [BTW you said A5 Bd but this should be the A3 bd i could only find U210 on A3, please confirm if I had another snr moment]. All tests carried out on A3. Im still not sure if the clock signal runs freely or is it looking for a good state from U220. I ask as Im getting ripple on the supply on U220. The main incoming feed is smooth but on pin 40 / 20 I get 20mv ripple , even if I short out L222 & L223.The lines between U220 & U210 look fine , either +5V or 0V or 20mv Ripple. I think unless there is an interlock stopping the clock I can only assume U210 is dead. If you agree then Ill send out a request for a broken A3 Bd and see if I can exchange U220 which will be fun. Many thanks, Ade. |
| Dr. Frank:
--- Quote from: Ade911 on July 08, 2023, 08:48:39 pm --- --- Quote from: Dr. Frank on July 07, 2023, 10:34:34 pm --- --- Quote from: Ade911 on July 06, 2023, 04:08:30 pm --- Hello Frank, No input, activating the Reset on the front panel All inputs now checked, On all devices you listed pin 1 gives 2 10us pulses from 0V to 4V, Pin 2 shows data stream, Pin 3 I cant read the clock maybe too fast for my old scope so sits high [+5v] and pin 15 is high [+5v] , started to try and test outputs which is difficult to achieve. Maybe its not a problem, A1 U10C, Im checking data coming from A1 U17 to the DAC but I dont see a W/R signal. U10 Pin 9 is connected to all devices just checked - PIN 1, I see 2 10us pulses as before , Pin 10 is sitting at 2V , the output A1 U10 Pin 15 just sits high even when Pin 9 goes above the 2V threshold , is this normal , I though being a comparator it would flip and drive to 0V. Anyhow Ill carry on checking the other outputs where I can of the devices you mentioned. Many thanks --- End quote --- Hi Ade, what kind of old scope do you have? Should be at least 20MHz BW, hopefully. The SR data might be clocked with 10MHz; I don't find the clock generator, or there should be a Hi speed UART on the analog side, which complements the UART A5U700, restoring clock and data, somehow. Well, that's the GA_Chip, A5U210, which serializes the data and creates all necessary signals for the different SR chains. It's clocked with 20MHz, so you should use a scope which has 60MHz Bw at least. This clock should be visible on all SR clock, and U10C serves as a simple inverter, delivering inverted clock for the DAC. Btw. there are ten SR '4094 in series on A1, in the following order: U1, U106, U307, U4, U14, U17, U6, U9, U201, U203. Check U203, pin 9, which is SERIAL OUT for the whole chain. If the clock signal is not present at all, and no data out at the last SR, then we might have found the problem. Frank --- End quote --- Hi Frank, Yes the clock is missing from U210 Pin 31, i traced and checked each signal back to the rear of U210 through R270,1,2 and the signal is missing [BTW you said A5 Bd but this should be the A3 bd i could only find U210 on A3, please confirm if I had another snr moment]. All tests carried out on A3. Im still not sure if the clock signal runs freely or is it looking for a good state from U220. I ask as Im getting ripple on the supply on U220. The main incoming feed is smooth but on pin 40 / 20 I get 20mv ripple , even if I short out L222 & L223.The lines between U220 & U210 look fine , either +5V or 0V or 20mv Ripple. I think unless there is an interlock stopping the clock I can only assume U210 is dead. If you agree then Ill send out a request for a broken A3 Bd and see if I can exchange U220 which will be fun. Many thanks, Ade. --- End quote --- Hi Ade, sure, should be on A3 board, sorry for that mistake.... you're really quick on the trigger to replace components. Please probe around that IC, if any other part is faulty, like U230, U131.. I can't hardly imagine, that such a part is gone. There's a 20MHz oscillator, search if you can find comprehensive signals around that. Please check pin 73, labeled IGCLK, if there's a clock available. |
| Ade911:
--- Quote from: Dr. Frank on July 08, 2023, 09:05:29 pm --- --- Quote from: Ade911 on July 08, 2023, 08:48:39 pm --- --- Quote from: Dr. Frank on July 07, 2023, 10:34:34 pm --- --- Quote from: Ade911 on July 06, 2023, 04:08:30 pm --- Hello Frank, No input, activating the Reset on the front panel All inputs now checked, On all devices you listed pin 1 gives 2 10us pulses from 0V to 4V, Pin 2 shows data stream, Pin 3 I cant read the clock maybe too fast for my old scope so sits high [+5v] and pin 15 is high [+5v] , started to try and test outputs which is difficult to achieve. Maybe its not a problem, A1 U10C, Im checking data coming from A1 U17 to the DAC but I dont see a W/R signal. U10 Pin 9 is connected to all devices just checked - PIN 1, I see 2 10us pulses as before , Pin 10 is sitting at 2V , the output A1 U10 Pin 15 just sits high even when Pin 9 goes above the 2V threshold , is this normal , I though being a comparator it would flip and drive to 0V. Anyhow Ill carry on checking the other outputs where I can of the devices you mentioned. Many thanks --- End quote --- Hi Ade, what kind of old scope do you have? Should be at least 20MHz BW, hopefully. The SR data might be clocked with 10MHz; I don't find the clock generator, or there should be a Hi speed UART on the analog side, which complements the UART A5U700, restoring clock and data, somehow. Well, that's the GA_Chip, A5U210, which serializes the data and creates all necessary signals for the different SR chains. It's clocked with 20MHz, so you should use a scope which has 60MHz Bw at least. This clock should be visible on all SR clock, and U10C serves as a simple inverter, delivering inverted clock for the DAC. Btw. there are ten SR '4094 in series on A1, in the following order: U1, U106, U307, U4, U14, U17, U6, U9, U201, U203. Check U203, pin 9, which is SERIAL OUT for the whole chain. If the clock signal is not present at all, and no data out at the last SR, then we might have found the problem. Frank --- End quote --- Hi Frank, Yes the clock is missing from U210 Pin 31, i traced and checked each signal back to the rear of U210 through R270,1,2 and the signal is missing [BTW you said A5 Bd but this should be the A3 bd i could only find U210 on A3, please confirm if I had another snr moment]. All tests carried out on A3. Im still not sure if the clock signal runs freely or is it looking for a good state from U220. I ask as Im getting ripple on the supply on U220. The main incoming feed is smooth but on pin 40 / 20 I get 20mv ripple , even if I short out L222 & L223.The lines between U220 & U210 look fine , either +5V or 0V or 20mv Ripple. I think unless there is an interlock stopping the clock I can only assume U210 is dead. If you agree then Ill send out a request for a broken A3 Bd and see if I can exchange U220 which will be fun. Many thanks, Ade. --- End quote --- Hi Ade, sure, should be on A3 board, sorry for that mistake.... you're really quick on the trigger to replace components. Please probe around that IC, if any other part is faulty, like U230, U131.. I can't hardly imagine, that such a part is gone. There's a 20MHz oscillator, search if you can find comprehensive signals around that. Please check pin 73, labeled IGCLK, if there's a clock available. --- End quote --- Hello Frank, Sorry I should have shared more testing results. A3 Board U230 20M oscillator OK, U131 OK , signal CK10 OK [ Not a square wave but still a clock pulse] . U211 , 212 change state during reset or changing front panel buttons, not sure if they have anything to do with how U210 functions. Unplugged P2 and P1 from the AC board to see if anything was affecting the signal DCCK_F [sitting at 5V] Where can I find the pin configuration of U210, I tried google but failed, guess Pin 11 U220 is acceptable - no clock , sitting at + 5V. U220 Pin 19 has a +5V clock pulse [more like a saw tooth] Good catch Frank, still learning from the master. Is this signal generated in U210 or U220 ? Tx Ade. |
| Dr. Frank:
--- Quote from: Ade911 on July 09, 2023, 09:06:43 am --- Hello Frank, Sorry I should have shared more testing results. A3 Board U230 20M oscillator OK, U131 OK , signal CK10 OK [ Not a square wave but still a clock pulse] . U211 , 212 change state during reset or changing front panel buttons, not sure if they have anything to do with how U210 functions. Unplugged P2 and P1 from the AC board to see if anything was affecting the signal DCCK_F [sitting at 5V] Where can I find the pin configuration of U210, I tried google but failed, guess Pin 11 U220 is acceptable - no clock , sitting at + 5V. U220 Pin 19 has a +5V clock pulse [more like a saw tooth] Good catch Frank, still learning from the master. Is this signal generated in U210 or U220 ? Tx Ade. --- End quote --- Pin configuration of U210??? It's on sheet 1 / 2of A3. What do you expect more? It's a hp programmed Gate Array, in my 3458A it's an ORBIT 6968A, don't know anything about this device. I have not measured inside my 3458A, but maybe the clock Pin 31 for the SR chain is only output, when needed. (*) Please scope on that pin, while you RESET the instrument, if there is an initial activity. What about pin 73, now? Is there a clock, or not? The 3458A currently does not work at all, anymore? Frank (*) That might be reasonable, so not to disturb the analog part by RF emission, during sampling. |
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