Note 8 - Share-based Compensation Plans - Stock Option Activity (Details) - USD ($)	12 Months Ended
	Dec. 28, 2024	Dec. 30, 2023
Exercised, shares (in shares)	0	(41,365)
The 2020 Equity Incentive Plan [Member]
Outstanding, shares (in shares)	903,500
Outstanding, weighted average exercise price (in dollars per share)	$ 2.66
Granted (in shares)	225,500
Granted, weighted average exercise price (in dollars per share)	$ 2.29
Exercised, shares (in shares)	(60,000)
Exercised, weighted average exercise price (in dollars per share)	$ 1.5
Forfeited, shares (in shares)	(69,200)
Forfeited, weighted average exercise price (in dollars per share)	$ 2.47
Expired, shares (in shares)	(61,500)
Expired, weighted average exercise price (in dollars per share)	$ 2.9
Outstanding, shares (in shares)	938,300	903,500
Outstanding, weighted average exercise price (in dollars per share)	$ 2.64	$ 2.66
Outstanding, weighted remaining contractual life (Year)	7 years 7 days
Outstanding, Aggregate intrinsic value	$ 17,197
Options exercisable, shares (in shares)	499,300
Options exercisable, weighted average exercise price (in dollars per share)	$ 2.51
Options exercisable, weighted remaining contractual life (Year)	5 years 9 months 3 days
Options exercisable, Aggregate intrinsic value	$ 16,742