Donations helped the Bradman Museum buy a collection of letters Sir Donald Bradman wrote over 70 years ago for almost $20,000.

Bradman wrote the letters to friend Bert Kortlang, a former Victorian Sheffield Shield cricketer, while on the Ashes tour of 1930 - his first tour overseas.

The collection of seven letters sold at auction for a total of $18,300.

Several other items, including programs, press passes and Christmas cards from Bradman and wife Jessie, were also sold at the auction.

Bradman Museum curator Richard Mulvaney said donations from the public had enabled the museum to be able to have the financial capital to purchase the letters.

The museum had originally said it could not afford the letters, but Mulvaney said the generosity of the public made it possible for the museum to make the purchase.

"I did not think that we would be in a position to find the financial resources to be able to be a bidder in this auction tonight," Mulvaney said.

"A number of people contacted the museum and felt that the letters rightly should be placed in the museum, and so basically the people of Australia have bought these letters."

In one of the letters, Bradman mentions a woman called Nina and asks Kortlang, who lived in London at the time, to help him arrange a meeting with her.

Bradman married Jessie the following year and they remained married until her death in 1997.

Brought to you by AAP © 2024 AAP