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Technical Question
#5

So I'm at about 14G. I was hoping it would be a bit heavier.

Post from Poor Poor little HRO

>Order came in today from Radiodazes. Some needed caps, rubber feet,and power cord. All of the pre war HRO's use a separate power supply. The earliest ones came with 2.5vac tubes. The reason I mention this is that the 2.5v tubes haul down A Lot of current. Set has nine tubes which equals about 11 amps of heater current. Meaning that the power cord has to be rather robust to handle the current. The OEM National power supply used a power transformer that has a 3vac winding to compensate for the voltage drop though the 4' cord.


The problem is it is difficult to find these days a cloth covered cable four conductor with two 20ga wire and two conductors that are 14  or 12ga to minimize the volt drop. After consulting with Henry over at Radio Boulevard
(Wonderful site for early SW radios) He's used 8 conductor cloth cover battery radio cable by tying 3 of the conductors together for each leg of the heater leads. Great idea.  

Tnx Mike it always good to have rocket scientist to consult with.

Terry 


Messages In This Thread
Technical Question - by Radioroslyn - 08-18-2015, 03:24 PM
RE: Technical Question - by OldRestorer - 08-18-2015, 03:33 PM
RE: Technical Question - by OldRestorer - 08-18-2015, 03:38 PM
RE: Technical Question - by morzh - 08-18-2015, 05:21 PM
RE: Technical Question - by Radioroslyn - 08-18-2015, 05:46 PM
RE: Technical Question - by OldRestorer - 08-18-2015, 09:44 PM
RE: Technical Question - by Radioroslyn - 08-18-2015, 09:53 PM
RE: Technical Question - by morzh - 08-18-2015, 11:04 PM



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