The board of National Guitars included John Dopyera, the inventor of the resonator guitar, his brother Rudy, Paul Beauchamp and Adolph Rickenbacher.
Legal wrangling ensued between Dobro and National. In 1932 Dobro won the rights and took control of National Guitars and renamed the company National Dobro.
WWII halted production.
In 1942 Louis Dopyera joined forces with Victor Smith and Al Frost. The combined first initials of their first names were blended into the acronym VAL Company or VALCO.
Valco manufactured guitars and amplifiers but did not sell them under the Valco brand. They acted as a jobber and sold many of their products through other companies.
Sears and Roebuck catalog
Prior to teaming up with Danelectro in the 1960's, most of Sears guitar amplifiers were manufactured by Valco.
In the 1940's and 1950's Oahu was a popular brand for Hawaiian guitar players.
These amps and steel guitars were manufactured by Valco, as were Airline, Custom Kraft, Harmony amps, Kay guitars and lapsteels, Penncrest and a slue of others.
During my research for Silvertone amplifiers I ran across an excellent web page called Silvertone World were I discovered the Danelectro Company was not the first company to produced Silvertone's amp-in-case, amp/guitar.
In the 1940's Valco produced an amp-in-case model for Sears/Silvertone. The amp/case came with an Oahu lap steel guitar.
Valco also produced the same amp complete with a Supro brand Spanish style electric guitar.
Both amp/cases were tube amps. It is my opinion the Danelectro is a cleaner, better designed model.
Danelectro guitars were very light due to the hollow body construction.
The case was medium density fiberboard, so it was much lighter than the wooden Valco case.
The Valco produced Supro/Silvertone case was made of solid wood. A wooden plank was placed between the guitar and amplifier to keep the guitar from the glass tubes.
Three of the photos were from Silvertone World web page. Check their web site out. It is excellent.