| Products > Test Equipment |
| Kontron/Tabor 6010 universal counter still worth getting? |
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| Hans81:
Hello, I am aware that the last entry is from 2018. I would like to rebuild the 1.3GHz option. Can someone tell me the value of the resistor R24. In the original schematic this value is unfortunately not mentioned. Thanks a lot |
| 0xdeadbeef:
Does this help? BTW: the manual does mention it, but as "SELECTED VALUE" |
| Hans81:
This is very helpful. Thanks for the very quick answer. |
| EyeDontKnow:
I took a chance and bought a Tabor 6020 parts unit with an "unknown problem". Before powering it up, I replaced all electrolytics because one was bulging. With power on, voltages checked good, and it booted as it should (almost, read on...) However, with a signal applied at the input(s), error flashes, "No Ref". It has the factory installed TCXO board. TCXO tests good at 10Mhz. At the ref-board to main-board junction, pin 6 should read 100Mhz. I'm getting a sine about 115Mhz @ 150mV P-to-P. For some reason the ref-board is not being recognized by the rest of the system. :-// During boot, it only says "6020" , and it should read "6020-1". |
| EyeDontKnow:
UPDATE: I believe I got it working. In the Tabor 6010/6020 manual, "Table 7-4 TCXO and x10 Multiplier Circuit Checks" (tcxo option)... my voltage and hertz readings were way off, especially on pin 6 (output) of the CA3140. It's used as a low-pass filter to the blah-blah-blah. Output on this opamp was wrong at -12v.... should be about -3.5v. I looked closely (like really closely with a loupe) and saw some whitish residue under the chip. I pulled the chip and added a socket. I had 2 old 3140's (used/pulls) so I inserted the cleanest one......but it had the same problem. Darn !! I also socketed and replaced a fresh 74HCT4046 PLL. Although.... on this factory board they used a 7046 PLL....difference being the 7046 has a "lock detector" output on pin 15 (which on this board is not used (left open). Still, no change. Near the end of my rope, I switched that CA3140 to my last and ugliest spare chip. Bingo..... no more -12v at the output......and a good 100Mhz @80mV sent out of the option board. It now measures freq, and without the "No Ref" error. The counter now works, though the boot-up display still does not indicate the option "1". I'll have to do a thorough Performance Check. =R= |
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