The Midgard™ features a high compliance voltage (3000 V) for injections from very small, or partially-clogged, pipette tips. The output current level can be regulated to +/- 0.5%, from 0.0 to 200 MegOhms.
Pulsed output helps avoid clogging or polarization of the tip of the pipette. The researcher may select pulsed or continuous current with a switch. The pulsed on/off times can be varied from 0.5 to 24 seconds.
Many researchers have requested external timing control for lab automation applications. The Midgard™ can be gated through a headphone jack, on the rear panel, by any laboratory logic pulse generator. The output current is continuous whenever the gating jack is logic high, off when it is logic low.
A touchpad switch allows reversing polarity. This is useful when using a retaining current to hold the pipette contents in the pipette during entry into the brain.
Tritiated prolineleucine. VM nucleus, thalamus. 1µA pulsed current, 10 minutes, 20 µ HRP in tris buffer, pH 8.6; rat; lateral habenula. 2µA pulsed current, 15 minutes, 12 µ pipette.
Load current fall time: 0.1 sec.
Load current rise time: Dependent on load resistance.