Discovery Geophysics
From: Discovery Int'l Geophysics Inc.
Brent Robertson
Box 57, Hague, Saskatchewan S0K 1X0
Ph: (306) 225-4422, Fax: (306) 225-4458
Dennis Woods, Ph.D., P.Eng.
14342 Greencrest Drive
Surrey, B.C., Canada, V4P 1M1
Ph: (604) 538-0900, Fax: (604) 538-0954
5 June 2006
The most recent TxII-3600 transmitter system, manufactured by Instrumentation GDD and capable of ~7.2 kW’s of output power at high voltages was used extensively by Discovery Int’l
Geophysics Inc during the winter of 2006.
The transmitter system involves setting up 2 TxII-3600 transmitters in series, one acting as a Master and one as a Slave, which is then powered by a 60Hz, 220V generator; to potentially achieve a high output voltage of 4800V. The aim to using this stateof-the-art transmitter system was to increase output current for a pole-pole resistivity survey carried out in an unusually harsh winter environment where often ground contact resistance is >50 k-ohm.
The system proved to be very reliable and effective in noticeably increasing output current in high voltage mode over other transmitter systems employed previously in the same environment.
Current stabilization was very good and current drift was generally <5% over a typical acquisition period of about 1 minute. The system is very operator friendly and well designed and no down time due to instrument malfunction was experienced over the duration of the fieldwork. Instrumentation GDD was exemplary in their interest and support and continually eager for feedback on the performance to assist if necessary.
Sincerely,
Brent Robertson
Operations Manager
Discovery Int’l Geophysics Inc.