James McPhail, 39, targeted the Halifax branch in Ashington after an unsuccessful raid at a nearby post office.
Prosecutor Deborah Smithies explained: "The defendant left his mother's address and cycled a short distance to Station Road. He had with him a long canvas bag inside of which was a long piece of wood.
"At about ten to noon he walked in the post office and went to the secure counter.
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"He handed a hand-written note which read: 'For the safety of you, your colleagues and your customers, just follow simple instructions as me and my partner outside have deadly weapons'.
“It continued: 'Please don't make us use them. Just pass over as many notes as you have to hand and we will leave peacefully’.”
However, the staff member pressed a panic alarm and McPhail fled empty-handed.
A couple of hours later McPhail walked into the Halifax and blocked the exit with a traffic cone.
Ms Smithies said he then passed another note to a staff member there which said: 'We have shotguns, pass over all notes right away or you and all customers in danger. Don't put lives at risk.'
Despite some money being hidden from him, McPhail ran off with a total of £3,065, but was later traced back to his mother's address via CCTV.
A victim personal statement from one of the Halifax employees said: "This has left me shaken and nervous about going to work."
Two months prior to the robberies, he also broke into a café in Bedlington where he caused £290 worth of damage by breaking a window and stealing a small amount of cash.
McPhail, of Seaton Avenue in Bedlington, who has 35 convictions on his record, pleaded guilty to robbery, attempted robbery and a non-dwelling house burglary.
He also had to be resentenced for an attempted burglary from last year.
Mr Recorder Ian Mullarkey sentenced him to seven-and-half years behind bars, adding: "The position is aggravated by your previous convictions and that you were intoxicated.”
In mitigation, the court heard McPhail was remorseful for what had happened and there was no physical harm caused by his actions.