  The Jupiter-family comet 103P/Hartley 2 (103P) was the target of the NASA
EPOXI mission. In support of this mission, we conducted observations from radio
to submillimeter wavelengths of comet 103P in the three weeks preceding the
spacecraft rendezvous on UT 2010 November 4.58. This time period included the
passage at perihelion and the closest approach of the comet to the Earth. Here
we report detections of HCN, H2CO, CS, and OH and upper limits for HNC and DCN
towards 103P, using the Arizona Radio Observatory Kitt Peak 12m telescope (ARO
12m) and submillimeter telescope (SMT), the James Clerk Maxwell Telescope
(JCMT) and the Greenbank Telescope (GBT). The water production rate, QH2O =
(0.67 - 1.07) x 10^28 s^-1, was determined from the GBT OH data. From the
average abundance ratios of HCN and H2CO relative to water (0.13 +/- 0.03 % and
0.14 +/- 0.03 %, respectively), we conclude that H2CO is depleted and HCN is
normal with respect to typically-observed cometary mixing ratios. However, the
abundance ratio of HCN with water shows a large diversity with time. Using the
JCMT data we measured an upper limit for the DCN/HCN ratio <0.01. Consecutive
observations of ortho- H2CO and para-H2CO on November 2 (from data obtained at
the JCMT), allowed us to derive an ortho : para ratio (OPR) ~ 2.12 +/- 0.59
(1sigma), corresponding to Tspin > 8 K (2sigma).
