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agenda log

1. 430 Transmitter

documentation - keep at it

magnet - get lower unit from Tab - check every winding of magnets for dc resistance and

inductance

meter relays - get them replaced!

modulator upgrade: separate fiber optic control lines to decouple the two decks.

Test procedures to trouble shoot the decks. Fiber optic monitor ports into the decks.

2. Tiedown system

lightning protection - move ground connections

encoder - lower voltage

digital noise - purge

servo loop - revisit theory

3. 430 transmitting from dome

turnstile

collector

waveguide installation

monoplexer driver

directional coupler to monitor tx power from Gregorian (move from the old OMT to one of the half-height sections feeding the dome).

4. Receiver cold load

electrical design

cryo design

Develop self-cal for Trcvr, i.e. Thot, Tcold, Tant switch built into the dewars.

5. Receiver calibration

does WTG have correct spreadsheet program? - old Trcvr calculation was wrong

Get a test dewar into operation. Improve heated resistor method to measure Trcvr.

6. VLBI

track Signatron progress & Haystack checkout schedule

build upstairs phase cal heads

7. Tertiary

8. Vertex Drive System: highest priority: working spares for PLC & LCU

Put the program development system(s) into good working order. Practice card swapping procedures.

9. finish monoplexer driver for 430 systems

10. reinstall hfss on repaired Dell computer

Week of Monday, 11-20-00 (3-day work week)

debug rotary floor failure - Mon. morning - no documentation available for

floor and tiedown disable/enable switches - had to trace cable thru trench

monoplexer driver

schedule haystack/signatron/trucking/airline

switch to andy's pc (take home zip disk and copy RSI drawing files)

tie down tension monitors

parts for 430 tx metering circuits - need these meters working to install new magnets

Week of Monday, 11-27-00 (5days)

Monday: work on total checkout of monoplexer driver

Tuesday: mount tension meters in tiedown systems and check manual operation (jumper)

Thursday: prepare for trip to Signatron- find all notes and doc. from prev. trip.

find list of deliverables - check tickets, cash, etc.

Week of Monday, 12-11-00

take Tuesday off

Monday: work on total checkout of monoplexer driver

Tuesday: mount tension meters in tiedown systems and check manual operation (jumper)

Week of monday, 12-18-00

drawings for second collector

Redesign totem pole circuit in monoplexer driver

prepare agenda for Klaus

spare cards

lcu pack, including irig reader

software flowcharting questions

vlbi - check progress with Signatron and Haystack (Dan Smythe)

dummy load for kollmorgen power supplies

az encoder error - ch end

vertex-vlbi-430tx-tiedowns-430greg(monoplexer)

regen card

Week of 1-8-01

monoplexer driver: made new floating deck design for 1 usec pull up.

troubleshoot markIs to get going on 430 from greg.

Sulzer's special filter - takes one LTC1562 (quad second-order filter chip)

+ a couple of op amps.

Week of 4-9-01

check on bill sisk's test set for regen cards & kollmorgen soft start circuitry

az encoder error, ch end

meter relays for 430

tie down ground connection for better lightning protection

tie down encoder power

tie down power for DAC board\

tie down noise environment in general

430 documentation - receiver cut off, blanking, interlocking

430 transmitting from dome - highest priority

need to troubleshoot VSWR chain. portable reflectometer needed. Network analyzer too heavy, can't be carried around, calibration is difficult.

Forget that for now; get up there and measure the reflection looking into the turnstile. Use the network analyzer and the half-height cal kit. Check the manuals for the analyzer to see if new manuals are clearer on setting up cals for waveguide standards.

12-13-02

Short term: 430 tx modulator modification: installation and check out

Medium term :

installation of new 430 tx timing system

monoplexer diode mounting: addinductance to resonate mica capacitors

recruitment: orgaize applications, determine whether we can send them a test.

proper procedures: everyone who passes up the process must pass through the test

front end page(s) to add to IF/LO block diagram set

3-20-03

Measure voltage levels from KlyA and KlyB reflected power detectors. Check out new reflected power meter. DONE

Meter relays

Lightning current fuse meters - Find total action through test cable - use to burn fine diameter cu. wire. Integral I^2 dt.

3-24-03 Mon

install y switch interlock cable to timing generator (1 hr observing lost yesterday when timing generator was left turned on). DONE

Finish refurbishing of arc detector chassis and sensors. DONE

Test reflected power inputs on new chassis. Turn on transmitter and measure reflected power detected voltage levels. DONE

4-21-04

List of 430 transmitter projects in order of priority:

rebuild monoplexer drivers

install monoplexer incident power monitors, maybe with connection to transmitter

fast shut-off

new crowbar driver

magnet current meter installation

calibrate beam supply voltage metering (HALF DONE)

install reflected power metering dir. coupler outside the xy tuner

install isolators at klystron inputs

dummy load: at least for low duty cycles (acid, y-switch, etc)

radiation smoke alarm - at least on mezzanine

new front panels for low level amp and low level modulation chassis.DONE

Caution signs for tie downs(DONE)

Danger! Do not work on or near anchor block when lightning is likely.

Peligro! No trabaje en o cerca del bloque del ancla ante la amenza de rayos.

Install field mill (or other robust E field monitor on tower top).

For the 430 console:

1. Some cooling system indicators: temperature, water level, and flow rate

2. Some diagnostic ability for the HV power supply: BNC test points from which to monitor the current in the various rectifier legs.

3. 430 transmitter: slow down the eh tuner motors

4. Question: does the mod anode run saturated, or will hum on the 1/2 voltage power supply tap cause beam modulation?

Get back to magnet current trip circuits.

See if Lisa has modified the IF/LO amp to reduce the reverse gain at the front panel monitor port.

battery-powered recording peak power meter to test whether receiving horns need shutter protection against S-band and its harmonics.