Pilot Wasp information required to identify model?

ID: 348480
? Pilot Wasp information required to identify model? 
13.May.14 04:38
86

Gary Cowans (AUS)
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Gary Cowans

Hi Everyone,

I have recently acquired a Pilot Wasp Radio and I cannot seem to identify which model it is exactly. I think it may be a combination of several models.

It operates from 240V AC and has a filter power supply using an 80 rectifier.

The Valve lineup is 39 36 76 41 80.

It also came with a box of plugin coils.

Any help will be greatly apreciated.

The pictures of the radio are attached.

 

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Super Wasp 
22.May.14 20:52
86 from 2643

Konrad Birkner † 12.08.2014 (D)
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Konrad Birkner † 12.08.2014

Hi,

the chassis is obviously from a Super Wasp (AC?), but with considerable modifications:

- as far as I can see your set uses similar coils for both the antenna stage and the detector stage. In the original Super Wasp the coils are different.There are separate sets of Antenna and Detector coils.

- what hppened to the Reaction capacitor lower centerline knob? The upper one is for filament control (rheo). But here it seems neither an original component nor the original function.
Could it be that the screen grid of the Det.stage is varied for reaction control?

- That leads to the next point: the original Det. triode is replaced by a tetrode which has a top contact for the screen grid. The base is compatible and the screen voltage is easily added overhead without RF problems.

- there is hardly a contemporary component left under the chassis. All newer parts.

My best estimation: A (later AC ?) Super Wasp (front and chassis tell it unambiguously) was upgraded using a screen grid detector tube. That permits better reaction control.

By no means an original series product. Too much modified.

OK?

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 3
Pilot Wasp 
23.May.14 02:00
99 from 2643

Gary Cowans (AUS)
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Gary Cowans

Thanks Konrad for your input.

You are correct it seems to be a K115 which someone has modified in the past.

When I acquired the set it had coils installed for 7 to 15mHz and the RF coil is slightly different to the detector coil in that it has a centre tap on the bottom coil.

I am in two minds as to what to do with it. Change it back to an original K115, or get it working as a screen grid detector.

What would you do?

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 4
Super Wasp 
23.May.14 10:10
109 from 2643

Konrad Birkner † 12.08.2014 (D)
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Konrad Birkner † 12.08.2014

Hi Gary,

from a second, closer look I came to the conclusion, that obviously the base plate was replaced to take an integral power supply, while the original employed a separate power pack K-111. Consequently the terminals became obsolete.

There is a main difference between K-110 and K-115 front panels: the upper center knob is with the K-110, but not found on the K-115. Hence the hole seen on your set indicates a K-110 front panel.

I would attempt a reconstruction towards a K-110 !. That seems to be the best chance to recover a historically correct appearance.
You would save the missing power pack.
The most important parts are present, let alone the reaction variable cap and the terminals.

A new base plate should not be a problem. I will make more pics of my own set to show the wiring.

On the other hand: what is beneficial to own (and even operate) a historically worthless (spoiled) radio?

What do you think about?

Kobi

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 5
Super Wasp 
16.Jun.17 03:47
976 from 2643

Gary Cowans (AUS)
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Gary Cowans

Well, a few years have passed and I have finally decided to make this radio a K-115 replica.

I have most of the major components and will only need to source period resistors and capacitors.

I will need a detailed view of the artwork for the front panel so I can replicate it.

I would appreciate any help fellow members can offer?

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