[ARC5] AVA-126 vibrator tubes

[Jack Antonio]

> On 1/17/2019 10:24 AM, Craig wrote:
>> Anyone have a supply of, or a source for the MI-19602-2 12 volt 
>> vibrator for an AVA-126A power supply? I recently managed to acquire 
>> one with an AVR-100 receiver, but it has the 6 volt vibrator tube. 
>> I've seen that someone does build a solid state replacement, but I 
>> haven't seen anything on how well it would work with the -126A. 
>> Cowtown Hamfest is this weekend, and I'll be on the lookout there too.


It took be a bit longer to dig up the information on the AVA-126 than
I thought, but finally got to it.

First, there is an AVA-126, and an AVA-126A. The difference is that the
A version provides for 24V operation. The changes in voltage are
accomplished by replacing the vibrator unit, and in the case of
24V operation, replacing the vibrator and some wiring changes.

Note that wiring changes are also necessary in the transmitter and 
receivers for operation on different primary voltages.

The RCA numbers are:

6V  MI-19602-1    RCA stock number 45301
12V MI-19602-2    RCA stock number 45302
24V MI-19602-3    no stock number given

The stock numbers are the numbers used when ordering
the units as replacement parts directly from RCA.

Comparing the basing diagram in the manual to the catalogs shows:

6V  OA or OA-1(depending on catalog, but I don't see a difference)
12V OB or OB-1

The 1946 Radiart Catalog shows:

OA  type 5355 for 6V
          5355-14 for 12V, but the still the same basing diagram,
                           so it wouldn't work in the AVA-126
                           or AVA-126A

OB  type 5356-14  for 12V
     type 5356-28  for 28V, but again, the same basing diagram
                            so wouldn't work in the AVA-126A

The above types are listed as Aviation types-nitrogen filled

However, the 1945 catalog does not show a cross reference
specifically to the AVA-126 or MI-19602 numbers.

The 1956 Radiart catalog shows:

OA-1  type 5510

OB-1  type 6511

Both types listed as aviation types, but no mention of nitrogen.

The 1956 Radiart catalog specifically shows these types as
replacements in the AVA-126, but says there is no replacement for
the MI-19602-3 24v unit.

My AVA-126A has a 5510 vibrator in it, but the bottom has been taken
off the the base and rewired to the 12V configuration, again, I don't
know what arrangements have been made concerning the coil.

I've never come across any replacements in years of searching, but
maybe the above information will help someone in their search.

Jack Antonio
WA7DIA