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Status

Partial replacement of old, lossy cables to RF cables
- Cable routing currently limited by available conduit space from the tunnels
Current cable assignment documentation is incorrect and does not match assignments or installation status
Initial waveforms taken with the Digital Analyzer were incorrectly saved and need to be re-taken
De-embedding of RF power levels measured outside of the tunnel yields un-realistic values:
- This will be further investigated at the next shutdown which will enable tunnel access
- Yellow tags attached to tunnel power detectors do not match loss values in official drawings
- Documented losses > 10 dB off expected values for worst offenders

	Cable	Status
AS1 Load FWD	103	Not installed
S Band Buncher FWD	100	Not installed
AS1 FWD	102
AS1 REV	104	**Mislabelled in W0440646 as 101
AS2 Load FWD	107
S Band Buncher REV	n/a	**Mislabelled in W0440646 as 104; no cable installed
AS2 FWD	106
AS2 REV	105	Cable damage suspected

Data

All data stored here
Cable Installation document here W0440646 - PLAN - SSD2025 - Cable removal and installation for LINAC LLRF System
Reference drawing
- LINAC tunnel 23W2495

Measurement Equipment

Equipment

Calibration and Settings

Peak RF Power Meter

Gigatronics

80350A/ 8652B

SN:1830822/8652601

Division and Department Space > LINAC System Peak Power and Waveforms > IMG_5543.JPG

Pulsed, RF triggered

Validated with R&S SMA100B pulsed RF output

Digital Serial Analyzer

Tektronix

DSA71254B

SN:8110800

Division and Department Space > LINAC System Peak Power and Waveforms > IMG_5540 (1).JPG

Relevant Interlocks

KLY FWD and REV signals are connected to interlocks internal to the modulators

Setup Notes

Signal	RF Cable from Tunnel	Tunnel Pictures
AS1 Load FWD	103 (not installed)	VIDEO DETECTOR #7
S Band Buncher FWD	100 (not installed)	VIDEO DETECTOR #4
AS1 FWD	102	VIDEO DETECTOR #6
AS1 REV	101 is listed in the cable installation notes, but cable 104 is actually installed. Cable 101 does not appear to exist	VIDEO DETECTOR #5
AS2 Load FWD	107	VIDEO DETECTOR #10
S Band Buncher REV	According to the cable installation notes, 104. No cable actually installed	VIDEO DETECTOR #3
AS2 FWD	106	VIDEO DETECTOR #9
AS2 REV	105** This cable is suspected to be damaged due to out of nominal losses at 500 MHz (27 dB) and 3 GHz (23 dB) and needs to be replaced	VIDEO DETECTOR #8
KLY1 FWD	108	MOD1 CP
KLY1 REV	109	MOD1 CP
Kly2 FWD	112	MOD2 CP
Kly2 REV	113	MOD2 CP
125 MHZ CAV	not yet assigned	?
500 MHZ CAV	not yet assigned	?
125 MHZ DRIVER FWD	not yet assigned	?
125 MHZ CAV FWD	not yet assigned	?
125 MHZ CAV REV	not yet assigned	?
500 MHZ DRIVER FWD	not yet assigned	?
500 MHZ CAV FWD	not yet assigned	?
500 MHZ CAV REV	not yet assigned	?

RF Power Level Calculations

Notes: These calculated de-embedded values are not consistently physically realistic; do not use these for any analysis or purpose.
Noted here as the investigation continues to determine the sources of errors in drawings and documentation.

Total Peak Power Summary
	Peak Power Measurement at Rack	Peak Power in Tunnel, De-embedded
	dBm	dBm	MW
AS1 Load FWD	6.8	109.9	97.3
S Band Buncher FWD	10.4	103.1	20.6
AS1 FWD	8.4	111.6	145.9
AS1 REV	-16.6	73.0	0.020
AS2 Load FWD	4.9	110.8	119.9
S Band Buncher REV	-14.9	61.9	0.002
AS2 FWD	10.4	113.5	225.4
AS2 REV	4.2	100.8	12.1

Losses
	RF Tunnel to Rack Cable Loss	Coupler cf	Installed Atten	Internal Cable Loss+Atten (per Tag)	Tag Total	Drawing Loss + Coupling Total	Total Loss + cf in Peak power Measurement used for de-embedding
	dB	dB	dB	dB	dB	dB	dB
AS1 Load FWD	16.83	53.26	33	32.99	86.25	83.82	103.08
S Band Buncher FWD	16.13	50.34	26	26.26	76.6	76.8	92.73
AS1 FWD	17	53.26	33	32.98	86.24	84.19	103.24
AS1 REV	16.13	53.26	20	20.24	73.5	71.44	89.63
AS2 Load FWD	19.87	53.2	33	32.82	86.02	83.82	105.89
S Band Buncher REV	16.13	50.34	10	10.26	60.6	60.8	76.73
AS2 FWD	16.83	53.2	33	33.1	86.3	84.05	103.13
AS2 REV	23.15	53.26	20	20.2	73.46	73.46	96.61