The POWER METER PROM (Option 02 only) contains a logic comparator (U21), a 2K x 8 PROM (U20), and a bus driver (U19).
The logic comparator is connected to the microprocessor address bus, and is configured to decode the 2K address range from 4000 Hex to 47FF Hex.
The comparator output drives the chip select of the PROM and the bus driver.
The PROM contains the Power Meter program as well as the power correction factors.
Bus driver U19 is used as a buffer for driving the microprocessor data bus
The power meter contains 690 correction factors. stored in PROM.
The 150 "power vs power" correction factors compensate for variations from
square law in the detector and power meter circuits. They are divided into
three tables. The first table corrects variations below 10 GHz. The second
corrects variations between 10 and 20 GHz. The third corrects variations above
20 GHz.
The 540 "power vs frequency" correction factors compensate for variations in
the detector output at different frequencies. "Power vs frequency" corrections
cover 0-27 GHz every 50 MHz. ' The power meter is calibrated at the factory
using specialized automatic test equipment.
Recalibration in the field is not recommended.
Has anyone ever tried this procedure on a 545B?
Hi,
54xA Opt.02 circuit doesn't work on 'B' model, the firmware part present in the Opt.02 EPROM is a extension firmware for the 54xA basic firmware and must be the same FW revision.
54xB firmware has already the option parts included, but it is normally disabled, the activation code reside in the CPU card EEPROM memory with the calibration table.
Do you have tried yourself?
I have not found anything (for now) in the manuals (the ones I could find) that would allow me to guess such a thing. For example, the 575B/578B service manual (ref. 5580032) also mention that "The PROM [on A107] contains the Power Meter program as well as the power correction factors."
Also, the A107 board in both manuals (545A and 575B) is referenced as 2020197-0X (with X from 1 to 8 depending on the combination of 10MHz ref and power measurement capabilities).
I also realized that the service manual for the 545A do explain the calibration procedure of the power meter in details (which the SM of the 575B does not).
EIP manuals, not the revisited Phase-Matrix ones available, are extremely confusing in the 'A' to 'B' transition, see the CCN number in first page, in case of 545 models this transition was occurred between CCN# 2009 to 2010 and for 548 between 2309 to 2310, BUT the CCN# 2009 545A (2309 548A) is the same hardware as the 54xB (new boards), the old hardware ends with CCN# 2008 (2308).
No, I have serviced professionally these counters 20 and more years ago.
Small gift:
http://www.ko4bb.com/getsimple/index.php?id=download&file=EIP_PhaseMatrix/EIP_545_548/EIP_545A_Service_Manual.pdf
This manual is for CCNs 2209/2309, usable for your 545B, CPU board is the new p/n 2020215, some layouts are not updated as the potentiometers on A108, but schematic seems to be correct.
I still have a few issues I need to fix:
- I've replaced the CR4 zener diode on A107; it was dead (open), but the sensibility remains too low on band 3 (I can sometimes "catch" a signal at -15dBm or so, but it's unstable). The reference voltages on pin 2 of U14 (LM393 comparator) is now a stable -100mV as described somewhere in the service manual, but the signal detection circuitry is still not working properly. I need to double check the capacitors on this A107 board, since a quick in-place check with a DER DE-5000 LCR meter showed some strange results for some of them (surprisingly, not the tantalum ones, but I'll check theses again with a lead desoldered from the board).
Have you checked the calibration on the YIG bandpass filter? If it's out of adjustment, the signal won't get through to the rest of the system or will be badly attenuated. I have a unit that seems to be made of pieces from multiple systems. The YIG filter was about as far out of adjustment as it could be!
Ed
Now i need to figure out where the calibration curves are stored in the memory. I don't think it's located at the same address as it was on the 545A (0x4000 in the EPROM that can be installed on A107) since the ROM on the CPU board do have content in this 0x4000->0x47FF mem area.
It might even be located in the EEPROM.
- When I power the device, it's set with a 200MHz offset and only 5 digits of resolution. I guess this is the part of the "SPECIAL WB68" version of the firmware I have, but I find it quite annoying.
Just realized HighPrecision wrote a few posts back the PM calibration table is in the EEPROM... doh! Whatever, I still need to find where.
I've found the tests vector table in the firmware, and there is no other (undocumented) test than the ones listed in the service manual (1 up to 11, 90 and 91). Could have been a 92 or any other value to enter a PM calibration menu but it seems no such menu exists... So one have to burn the values in the EEPROM somehow.
Special WB68 is a BAND 3 Low end frequency extension to 0.6GHz (600MHz) with reduced specs for sensitivity and power meter dynamic range.
Frequency offset and resolution setting have not to do with this special option, in the EEPROM there are saved the instrument power-on defaults.
As I said the power meter calibration is NOT part of the standard calibration procedure, there is no related TEST xx for this.
The EEPROM on CPU board is allocated from 0x0800 to 0x0FFF
Power meter calibration table start at 0x0810
YIG DAC calibration table start at 0x0C00, but I have no idea if the special option WB68 start at this location (shifted data ?).
You can use TEST 10 to modify the EEPROM locations, or via GPIB with TA10 command, obviously the write-protect switch should be disabled.
I suggest to save the entire EEPROM before any attempt to change data.
Another question, maybe I missed this in the service manual, but is there a procedure to check wheter the YIG calibration is correct?
I was thinking about how I can check this (to address my sensibility problem), and I'm not sure what's the best way of doing this verification.
Don't think I can force the YIG to stay centerered at a given freq, without scanning (then inject a know signal and measure the power ouput from A203. Can I? Setting the low/high freq limits to the same value maybe?
David
Another question, maybe I missed this in the service manual, but is there a procedure to check wheter the YIG calibration is correct?
A quick method only to verify if the YIGF is correctly centered, is to inject a small bipolar current into feedback node of U3 OP-Amp on A108 board, in example: a potentiometer between +12V and -12V, the wiper connected with a reasonable high value resistor in series to the (-) input of Op-Amp.
Thanks a lot. Pretty obvious once one does look at the schematics of the YIG driver... I'll give a try ASAP.
Another weak point maybe the YIG current sense resistor (the big one on A108) is out of tolerance.
Special WB68 is a BAND 3 Low end frequency extension to 0.6GHz (600MHz) with reduced specs for sensitivity and power meter dynamic range.
Frequency offset and resolution setting have not to do with this special option, in the EEPROM there are saved the instrument power-on defaults.
WB-68 B3 .6GHZ to 20 GHZ
600 MHZ to 1 GHZ 0 to -20 dBm
1 GHZ to 20 GHZ +5 to -20 dBm
BCD remote programming (this is a special on a 545B)
GP-IB (option 08)
instrument configurated with BCD interface. GP-IB board
and rearpanel cable physically located in unit.
BCD to GP-IB and vice versa can be done within 15 min.
That's all, this option is possible ONLY on 545B and not on a 548B, the extra space for YIG DAC calibration (to 26.5GHz) is used for this low end extension, probably data shift as I said.Code: [Select]instrument configurated with BCD interface. GP-IB board
and rearpanel cable physically located in unit.
BCD to GP-IB and vice versa can be done within 15 min.
when locked on a (strong enough) signal on band 3, the IF sits at roughly 127.9MHz instead of 125MHz as described in the manual, for which the troubleshooting tree concludes that "VCO or LOCK CIRCUITRY on A108 BAD".
127 MHz is correct, EIP has changed IF frequency in later A203 revisions, all 'B' models are 127 MHz.
You can look at the A203 internal IF amplifier, if I remember correctly at right side looking from front, sometimes I've found some leaking SMD ceramic capacitors. Please DO NOT touch the small wires coming from YIG filter through a hole, these are folded as a kind of inductance during factory calibration.
Check also if the screws holding the YIG filter to A203 box are tighten, sometimes loss of performance happen for these loose screws.
There are a few of the on eb, but none have exactly the same part number. For example there is a reasonably cheap 2010241-08 Rev. D available, is there a chance it will work (after recalibration)?
Should I try to stick it back to the holder? With what kind of "glue"? For the record, these 2 balls are very small, maybe 2 or 3/10 mm, so it will not be an easy task...
Ok I'll be extra careful! How leaky are we talking about there? like they begin to behave like a resistor on DC?
[mode miracle]Don't you have a copy of the 545B service manual somewhere? It would be so much easier! [/mode miracle]
If you have the possibility to measure the input RL (VSWR) setting the YIG coil current for a specific tune frequency, you can determine if the coupling between input RF link (that is critical) and the YIG sphere is compromised or not.
I have some in paper form, unfortunately NOT in pdf, another member has already asked me for a manual, at the moment don't have much time to do long and tedious scanning sessions...
The YIG sphere is typically mounted on the end of a thermally conductive rod (normally beryllium).
This is done for two reasons: 1) the rod acts as a “tuning stick” for orienting the YIG sphere in the resonant circuit and
2) YIG has best performance when it’s temperature is kept constant.
What is the best way of setting the YIG current to match a given frequency (bypassing the automatic search mechanism)? I don't see any TEST mode for that. Could the min/max frequency parameters be used to achieve this?
but using TEST10 (memory read/write). According to the SM, it seems possible to directly write into the YIG frequency controller (at addresses 0x1840 and 0x1842); for a desired frequency F (in MHz), just have to write F/2 as hex value in these registers.
The programmable VCO signal (370-500MHz) need to be raised in power to have sufficient level to drive the SRD (Step-Recovery Diode), to obtain a wide comb of carriers (multiplies of VCO carrier), after this there is another circuit with the microwave mixer.
In some occasions, the old variant of A203 MW converter (2010137-xx) may have problems with two trimmer capacitors around the VCO power amplifier, turning these usually resumes SRD RF drive power level and consequently the sensitivity of counter.
Where is this SRD located? on the A201-A (VCO) board or in the A203 YIG assembly itself (on the ceramic board embedded in the YIG filter assembly)?
BTW, on my unit, the big black resistor near the output 2SC2283 power transistor, can turn very hot, around 150°C; not sure it is expected or a sign of leakage somewhere. The resistor does not seem to suffer, however, from this (it looks physically and electrically OK).
The SRD is obviuosly part of the microwave circuit, I assume is located on LO side of ceramic microcircuit at opposite side of directional coupler, I barely see, on your photo, a complex microwave circuit with inductances, stubs, capacitors, the SRD diode is located here.
Coupling side of the coupler receive the comb signal from LO and is terminated at ground side with a resistor, probably 50 ohm and a laser trimmed capacitor.
LO signal is directionally injected to main side of coupler toward the mixer diode, also on this main side of coupler pass the YIG filtered input signal to mixer.
Just after the mixer there are two small wires for IF output signal (127MHz).
This resistor is connected in series with a inductance to the RF power transistor collector terminal to feed supply current from the +12V power rail, heating of resistor is NOT normal at 150 degrees level, measure the voltage drop on resistor and the resistance value, it should be 10 ohm.
Try to short the base terminal of 2SC2283 to ground and verify if the voltage drop on resistor goes to zero volts, shorting base to ground removes BIAS voltage from resistive divider, if the voltage drop on resistor remains high the RF transistor is probably damaged.
I've had a look at EIP 575 Service Manual and found Error 40 code means DAC table Error.
Thus, if this Service Manual can be used for my 545B I'll be able to repair it. At least I have to dig a bit more onto A107 board now.
douardda, Did you get the YIG working in your counter? If not, I have a 545 that I got in pieces and I have an extra YIG oscillator and it appears to be in good condition. I think it may have option2 in it as well.
douardda, Did you get the YIG working in your counter? If not, I have a 545 that I got in pieces and I have an extra YIG oscillator and it appears to be in good condition. I think it may have option2 in it as well.
douardda, Did you get the YIG working in your counter? If not, I have a 545 that I got in pieces and I have an extra YIG oscillator and it appears to be in good condition. I think it may have option2 in it as well.
Hi, yes I have the power meter working. I made some hardware modification on A107: add an AD7524 (U12) , removed R39 and installed a detection diode (I used a QSCH1245 instead of the original FH1100).
I've had a look at EIP 575 Service Manual and found Error 40 code means DAC table Error."DAC Table Error" is apparently an access problem to calibration data stored in A105 EEPROM, Error 32 is also suspicious related. Check all power supply voltages on main board, not directly on power supply board, often there are problem on connectors contacts to board edges.
Also check for possible data/address BUS overloads from PIA chips (68B21).QuoteThus, if this Service Manual can be used for my 545B I'll be able to repair it. At least I have to dig a bit more onto A107 board now.Yes, this manual is usable.
3F FF 3F FF FF FF FF FF |
Hi Guile,
DAC Table is clearly incomplete, looks as a aborted TEST 90 calibration process, missing the DEF-2 bytes before 'Table End'.
If you have the required generator do a complete recalibration via TEST 90 as described on 575B manual, at 20 GHz point there is an error, with generator @ 20GHz the frequency inserted is 18 GHz, that is wrong, must be the same frequency of the generator.
If you are unable to do the complete calibration, try to modify EEPROM locations from 0x0C10 as:
3F FF 3F FF FF FF FF FF
Also the 600MHz is not a standard cal point for plain 545B without special options.
Sorry, I'm a bit late to this party.
I've got an EIP 575 which I'm planning to implement the power meter on, I've all the parts, just no time.. sigh..
I thought for future reference I'd add a link to the python script I wrote to use the TEST 10 process over GPIB to read out EPROMs. I was verifying my images matches the "Rev D" set available online. This can be adapted to read out what ever memory range you want.
https://github.com/AshleyRoll/GBIPLogger/blob/master/eip575_memory_reader.py
Note that I'm using a Prologix Etherent GPIB device, but you can modify the code or add drivers as needed to my hacked up code DM me if you need help.
Hope it helps someone.
Ash.
Sorry, I'm a bit late to this party.
I've got an EIP 575 which I'm planning to implement the power meter on, I've all the parts, just no time.. sigh..
...
Thanks for proposing your help Ash, but I've also developed similar script to dump my EEPROM. However if you can share with me your EEPROM content (from 0x0800 to 0x0FFF) I'll be very grateful!!
Now I need to recalibrate my counter again but I'm still interested with activating the Power Meter. Let's try together if you agree
Sorry, I'm a bit late to this party.
I've got an EIP 575 which I'm planning to implement the power meter on, I've all the parts, just no time.. sigh..
...
Thanks for proposing your help Ash, but I've also developed similar script to dump my EEPROM. However if you can share with me your EEPROM content (from 0x0800 to 0x0FFF) I'll be very grateful!!
Now I need to recalibrate my counter again but I'm still interested with activating the Power Meter. Let's try together if you agree
Hi Guile,
I figured you had already done something similar, but I thought I would leave the code here for others in the future
I'll dump our the calibration data for you over the weekend. Hopefully it matches the memory range you expect. Mine is a 575, not a 545B however...
If you haven't seen it, here is another person adding the Option 2 power meter..
http://www.simonsdialogs.com/2014/09/eip-545a-microwave-counter-power-meter-upgrade/
I was planning on documenting and sharing my progress on the upgrade, so more than happy to work this out together
Cheers,
Ash.
Thus, regarding to 545B I need to find a way to activate the power meter (removing the Error 13). I'm wondering if computing the correct checksum like indicated by 545A SM would suffice to activate it?
Thus, regarding to 545B I need to find a way to activate the power meter (removing the Error 13). I'm wondering if computing the correct checksum like indicated by 545A SM would suffice to activate it?
Hi Guile,
For 'B' models, and more confusing for last CCN number of other non-B models, equipped with new A105 CPU card (2MHz clock) it's NOT necessary to calculate the checksum and nor to write related location.
For Opt 02 activation you already know the modifications to A107 board to add missing DAC chip and remove/install components as explained by douardda, yes also the R40 has to be removed.
Give me your data in EEPROM locations from 0x0800 to 0x080F and I'll try to suggest the possible modifications for option activation
Thanks for proposing your help Ash, but I've also developed similar script to dump my EEPROM. However if you can share with me your EEPROM content (from 0x0800 to 0x0FFF) I'll be very grateful!!
Now I need to recalibrate my counter again but I'm still interested with activating the Power Meter. Let's try together if you agree
Cheers
So, on my unit the entire range between 0x0800 and 0x0FFF is "blank" (0xFF). It doesn't appear to have any non-volatile ram, at least in that range. I guess my entire memory map is different that I have found in the available service manuals..
My EIP 575 has A105 (CPU) board part number 2020195 (-01 hand written) if that helps at all.. probably not..
Maybe HighPrecision can shed some light on the older '575 units?
The model and serial numbers read:
Mod: 575 CCN 1802
Thanks for proposing your help Ash, but I've also developed similar script to dump my EEPROM. However if you can share with me your EEPROM content (from 0x0800 to 0x0FFF) I'll be very grateful!!
Now I need to recalibrate my counter again but I'm still interested with activating the Power Meter. Let's try together if you agree
Cheers
So, on my unit the entire range between 0x0800 and 0x0FFF is "blank" (0xFF). It doesn't appear to have any non-volatile ram, at least in that range. I guess my entire memory map is different that I have found in the available service manuals..
My EIP 575 has A105 (CPU) board part number 2020195 (-01 hand written) if that helps at all.. probably not..
Maybe HighPrecision can shed some light on the older '575 units?
The model and serial numbers read:
Mod: 575 CCN 1802
SER: 00671
Ash.
My EIP 575 has A105 (CPU) board part number 2020195 (-01 hand written) if that helps at all.. probably not..
Maybe HighPrecision can shed some light on the older '575 units?
Hi Ash,
Between A105 old type (2020195-xx) and new type (2020215-xx) cards the memory and peripherals map is completely different, only the new 2020215 has one (EE)PROM (e2prom) allocated from 0x0800 to 0x0FFF (X2816A 2Kbytes type).
Old cards don't have any non-volatile configuration/calibration storage, only UV Erasable (E)PROM, 2516 or 2532 ancient types, the new card use three 27C128 UV (E)PROM with all option firmwares fitted.
On old card the options are added by additional UV (E)PROMs in related empty sockets as firmware extensions, for Opt.02 (Power Meter) is installed on A107 and contain either calibration table AND the PM firmware, it's important that the firmware is the SAME revision letter as the base firmware on A105 old type. For this reason Simon sells the entire set of (E)PROM (base + PM extension with cal data), obviously that CAL data isn't optimized for all counters, but only for the original calibrated unit.
Your EIP counter is a very early CCN#, this model (18GHz) was started with CCN:1800 in production and got new A105 card at CCN:1808, from CCN:1809 are all 575B models.
Thanks to my blank EEPROM your results are really close to mine now Thanks a lot for having tried!
Thus if I understood correctly what HighPrecision said, it looks like that what you have to do is to buy some EEPROM, DAC, and diode and program them with the available files online.
By the way I know now that my model is 545B CCN 2213 and I have option WB68 installed.
Good luck for your modification !
Thanks Guile, Hope you managed to find a way to fix yours as well!
Cheers,
Ash.
Do you know of any service documentation that better matches my model?
@HighPrecision: I owe you a beer!! If you're coming in Nice one day let me know I'll fulfill my promise then
Cheers
Do you know of any service documentation that better matches my model?
Hi Ash,
best available match is the 545A manual for CCN:2205, all cards, except A103 and A104, are pratically the same part number suffix (revision), I've uploaded here:
https://www.dropbox.com/s/hmu2vq9ew4fcaun/545A-548A_Manual_5580021-04_Apr83%20%28CCNs%202205%20and%202305%29_2nd%20Ed.pdf?dl=0
For A103 and A104 cards please refer to the available 57xB manual.
But I need first to fix my EIP again as I'm no more able to read a thing from GPIB while writting works partially. Maybe a bus driver is faulty on the A101 board ( )
That's odd ?
Just went into the workshop it is a 548A, options 02, 06 serial number 02063 ccn 2309 or maybe 2307 ?
Sensitivity on 2.7Ghz -32dBm
6125 LDX #M005D ;8E 00 5D
6128 LDA #$0D ;86 0D
612A STA $01,X ;A7 01
612C LDA #$05 ;86 05
612E STA >M0045 ;B7 00 45
There is however very important function called right after.6131 JSR Z66FB ;BD 66 FB
This function will commit the resolution value to various places, probably for counter chain. I have traced the gpib commands and from there i have found how resolution is set.612C LDA #$00 ;86 00
612E STA >M0045 ;B7 00 45
6131 JSR Z66FB ;BD 66 FB
eeprom offsets:
0 - set to 0x00 to enable power meter option
2 - set to 0x5a to enable DAC option
3 and 4 set to 0x35 and 0x59 for some magic (probably band 4 operation, I have not traced this, not sure what it does)