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-   -   Dumont RA-400 (http://www.videokarma.org/showthread.php?t=259479)

Kiwick 09-12-2013 07:55 AM

Dumont RA-400
 
3 Attachment(s)
Hi,

i recently found this Dumont RA-400 set on the curb, it's in poor conditions with peeling veneer and a lot of missing tubes, but the CRT is still intact and it seems to be a low hour set judging on how clean the HV cage is inside.

This set was made for the Italian market and was apparently assembled in Italy using italian-made components and has Philips speakers in a separate bass reflex compartment, it also has a voltage selector to enable it to be used on 120,160,220 and 240v power.

is this a clone of an american Dumont set?

dieseljeep 09-12-2013 08:58 AM

Quote:

Originally Posted by Kiwick (Post 3081978)
Hi,

i recently found this Dumont RA-400 set on the curb, it's in poor conditions with peeling veneer and a lot of missing tubes, but the CRT is still intact and it seems to be a low hour set judging on how clean the HV cage is inside.

This set was made for the Italian market and was apparently assembled in Italy using italian-made components and has Philips speakers in a separate bass reflex compartment, it also has a voltage selector to enable it to be used on 120,160,220 and 240v power.

is this a clone of an american Dumont set?

It sure looks like the last of the Dumont sets, that were built here.
They had a separate power chassis. Also, the control panel is very similar.

Kiwick 09-12-2013 10:09 AM

we apparently had Dumont sets built here in Italy until about 1972, the last ones had a cheapish 7-tube hybrid chassis

this one has "high fidelity" written on the CRT bezel, a few knobs hiddend behind a metal door on the front panel, and a "dumonitor" control behind.

maybe someone has a tube placement chart for this set? mine is missing about 2/3 of them :thumbsdn:

dieseljeep 09-12-2013 10:52 AM

Quote:

Originally Posted by Kiwick (Post 3081987)
we apparently had Dumont sets built here in Italy until about 1972, the last ones had a cheapish 7-tube hybrid chassis

this one has "high fidelity" written on the CRT bezel, a few knobs hiddend behind a metal door on the front panel, and a "dumonitor" control behind.

maybe someone has a tube placement chart for this set? mine is missing about 2/3 of them :thumbsdn:

Your set might use the European type tubes, that many of the American sets, didn't use.
The USA Dumonts used 6BZ6's in the IF, video out would a 6AW8 or a 12BY7, horiz out would be a 6DQ6, damper, a 6DE4.
Dumonitor is an AGC or a noise gate control. A great performing set! :thmbsp:

Kiwick 09-12-2013 03:51 PM

this one uses american type tubes, the later hybrid dumont sets used european tubes instead

wa2ise 09-12-2013 04:03 PM

Looks like they went to some effort to minimize the impact of stray magnetic field from the power transformer, from the angle the transformer is mounted on that chassis.
http://www.videokarma.org/attachment...9&d=1378990486

dieseljeep 09-14-2013 09:31 AM

Quote:

Originally Posted by Kiwick (Post 3081978)
Hi,

i recently found this Dumont RA-400 set on the curb, it's in poor conditions with peeling veneer and a lot of missing tubes, but the CRT is still intact and it seems to be a low hour set judging on how clean the HV cage is inside.

This set was made for the Italian market and was apparently assembled in Italy using italian-made components and has Philips speakers in a separate bass reflex compartment, it also has a voltage selector to enable it to be used on 120,160,220 and 240v power.

is this a clone of an american Dumont set?

I pulled the Sams on the RA400, dated 7/58. Your set looks identical.
Was the TV system used in Italy, at the time the set was built, referred to as CCIR?
Also, where did they use 160 volts? :scratch2:

Kiwick 09-25-2013 08:35 AM

we had CCIR-B TV broadcasts in Italy indeed
http://en.wikipedia.org/wiki/CCIR_System_B

depending on the area and power company, we had 110, 125, 160 and 220v power here in Italy until the nationalisation of all power companies into the Enel state power company in 1962,

but some rural areas continued to use these oddball voltages up to the early 70s until all old utility transformers were replaced, some remote areas even had DC power from small hydro plants

also the line voltage was quite unstable back then so most people had to use saturated core reactors to power their TVs.


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