Main INDEX
Monthly INDEX
PREV
NEXT
User name Xf. Zhu, X. Zheng, W. Korsch
Log entry time 13:20:08 on July18,2001
Entry number 66623
keyword=Target - EPR: 40.0 %
12:45 pm EPR measurement
Conditions: beam on, cell position: reference cell, B-field: 0 deg, lasers #5,6,7 on,
all grad. coils off
1st
down: freq. shift = -44.01 KHz +/- 1.67 KHz, P = -40.19%+/- 1.52%
up: freq. shift = 42.80 KHz +/- 1.76 KHz, P = 39.09%+/- 1.60%
0th
down: freq. shift = -44.68 KHz +/- 1.65 KHz, P = -40.80%+/- 1.51%
up: freq. shift = 42.31 KHz +/- 1.75 KHz, P = 38.64%+/- 1.59%
Comments: We did not find an EPR signal for quite a while; tested Lockin
amp., checked outputs of Wavetek, SRS FG, everything ok. Finally we looked at
output from PI feedback box (with modulation signal connected only), output
signal looked quite noisy, disconnected V_mod. input and reconnected it
again, then D2 appeared.
Best guess for problem: oxidized contact of V_mod input.
NOTE: Lockin AC gain: 40dB / Input limit: 30mV now .
(all other EPR prms were as before).