The main unit serial number is B108698 the serial number of the 177 is B059769
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On 2/14/2020 4:48 PM, Eric via Groups.Io wrote:
Mine is defiantly the new style. The cap I am having trouble with is the user adjustable one on the front of the case. It does not have the 2 screws It has the panel mount nut. I will look up the serial number on the fixture when I get home but if memory serves it is a 50xxxx fixture.
On 2/14/2020 3:48 PM, Mlynch001 wrote:
Looking at the schematic in my copy of the manual, I see that there is Text Box indicating "LOOPING COMPENSATION" with an arrow pointing above and to the right at C632. C630 is a smaller trimmer cap used for the Looping calibration procedure Step 4 (Pg 5-6 + See Manual Change pages), it is located below and to the left of that test box in the schematic, not very clear on some scans of the manual. C630 is accessible through a hole in the bottom of the 177 fixture. Bothe C630 and C632 are mounted in the 177 Fixture, and C632 is definitely the operator adjustable front panel looping control cap. C630 changed a couple of times through out production as well. Looking at the Mechanical Parts list on my 177 Service Manual, it appears that only the first 215 units used the 4-40 screw mounted Looping Comp Cap. After S/N B010316 they used a single nut and washer on the threaded neck of the compensation cap to secure it to the chassis. Always good to have the serial number of your unit(s), especially with the 577/177 combination. It is possible to mix early and late models of either component on this unit. It is possible to have a very old 577 with a very new 177, or vice-versa. This is something that I ran into on my units, since I obtained them from two different sources.