Note 6 - Line of Credit

12 Months Ended

Dec. 31, 2017

Notes to Financial Statements

Debt Disclosure [Text Block]

6.

Line of Credit

On

March 29, 2006,

we entered into a Loan and Security Agreement with Silicon Valley Bank (“SVB”) to establish a

$1.0

million line of credit (the

“2006

Credit Line”).

The Loan was renewed annually until

2016.

On

June 21, 2016,

the Loan Agreement terminated.

Due to increasing fees associated with the Line of Credit, we chose

not

to renew the loan agreement on the termination date. We replaced the line with an increased commitment under the CEO Note (Note

7

below) as needed.