HP 8643A
First Catalog | 1992 |
Last Catalog | 2001? |
Frequency Range | 0.252 - 1030/2060 MHz |
Amplitude Range | -137dBm to +13dBm |
The 8643A signal generator is closely related to the 8644A/B, 8645A, 8664A, 8665A/B .
In that family, the 8644A, 8645A and 8665A were all released together in 1989 (see also HP Journal issue from October 89). The 8665B appeared in the 91 catalog. The 8643A, 8644B and 8664A appeared in the 92 catalog :
The HP 8643A 1 GHz/2 GHz and HP 8644B 1 GHz/2 GHz RF signal generators are replacements for the HP 8644A. […]
Specifications
Options
001 High stability time base with EFC
002 2060 MHz doubled output
003 Rear panel input/output
004 Low noise option
005 Electronic attenuator (N/A with Option 002)
008 Pulse modulation
009 Specified VOR/ILS
010 Reduced leakage configuration
011 2 GHz internal frequency counter
907 Front handle kit (5061-9690)
908 Rack flange kit (5061-9678)
909 Combined front/rack flange kit (5061-9684)
(these two are from some test equipment vendor's page, I could not find an official source)
Manuals
HP 8643A, 8644B
Quick Reference Guide. First edition 08643-90019 / 08643-90020
Download @Keysight
HP 8643A, 8644A/B, 8645A, 8664A, 8665A/B
Assembly Level Repair , PN 08645-90145 . (Serial numbers: <= 3246A (8643A), <= 3203A (8644*/8645), <= 3744A (8664/8665*))
Download @Keysight, or
Download here
HP 8643A and 8644B Synthesized signal generator. (Serial numbers 3147A and above).
User's guide, PN 08643-90019 (why is it the same PN the quick ref guide ?)
Download @Keysight , or
Download here
HP 8643A, 8644B, 8664A, 8665A/B
Data Sheet , 5091-2580E,
Download here
08643-90022 Installation notes,
Firmware Upgrade Kit 08643-61018 for the HP 8643A Synthesized Signal Generator
Download @Keysight
Firmware versions
Revision code | Date code1) | ROM Partno 08643-X | Reason for change |
3.3.0 | 2908 | 87001-87004 | Original release of the firmware. |
4.0.0 | 3203 | 87101-4 | Adds firmware to control the new timebase configuration. Corrects the following special functions: 160, 162, 171, 320, 331. Adds special 328: user enabled transient error interrupts. |
4.2.0 | 3409 | 87201-4 | Fixes center frequency accuracy in FM Mode. Corrects counter diagnostic error 18999. |
4.2.1 | 3449 | 87301-4 | Corrects the calibration error due to the differences between the ALC EEPROMS. Added a diagnostic latch to the ALC module. Fixed a potential divide-by-zero error in the attenuator driver module. |
8643A DCU ROM 4.2.1 @ KO4BB
repair & misc info
The DCU card has a Ni-Cd battery pack, prone to leaking and damaging PCB. Symptoms of memory loss : unit does a self-calibration (5-7 minutes) on every power-up.
The RAM battery voltage is routed through the motherboard, so removing the DCU clears RAM automatically (and causes a self-calibration on next powerup).
A few RIFA caps, and leaky LXF / TXF electrolytics in the power supply modules.
Look out for shorted tantalum caps (Kemet T396 series, 3 legs) where subjected to inrush current (i.e. power entry in the various modules)
The attenuator card has an EEPROM holding calibration data
Youtube repair videos :
Photos of internal modules