Roy Edwards has kindly sent these photographs of his father's banjo with the following comments

 I have just stumbled across your fascinating web site dedicated to the Zither banjo whilst researching the history of my fathers old five string banjo which I have inherited.  It is stamped on the headstock 'JETEL 3507'  and lower down at the back it is stamped 'GREENOP PATENT'.  It also has a highly polished chromed metal back.
I have ascertained that both Jetel & Greenop were manufacturers of banjos & wonder why it has both brand names thereon. Is anyone able to give me some information regarding this?
My father had band in the late 1920's early 30's named 'The Ruby Orpheans' (why that name I don't know either) and I have some photos of him with them if it is of any interest to you for your web site.  He was only an amateur but very popular in the north London area at the time & did many concert parties & wrote quite a few of his own songs & 'plays'.
Thanks for the information, Roy.

A.P Sharpe provides the following information about Greenop

Norton Greennop was born in 1868 and was closely associated 'with the fretted instruments for over forty years. he played the banjo with the Moore & Burgess Minstrels and The Stavordales but was more widely known for his long partnership with Arthur Stanley Sr.  The team of Stanley & Greenop toured every Music Hall in the United Kingdom from 1903 more than once and even did a tour of South Africa.  The partnership broke up just prior to the outbreak of World War 1. At the turn of the century, Norton Greenop designed and sold the first banjos to bear his name as maker but these instruments were made for him by John E. Dallas.  They included several unusual features and were a cross between a banjo and a zither banjo with a lot of metal in the hoop.  The tone was inclined to be metallic. In 1926 John Alvey Turner Ltd. were agents for his "Tonetube" banjos, plectrum- banjos and tenor banjos.  Again this was a zither-banjo type of instrument, the brackets passing through circular tubes which were said to add tone to the instrument, "functioning as the sound post of the violin".  Instead of the hoop being enclosed at the back (ala zither banjo) it had a concave "receiving pan" insert "to project the tone forwards." At this time Norton Greenop was carrying on a music business at Leigh-on-Sea, Essex and conducting his own dance band. He died on December 27th, 1930, after playing at a dance.

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