What do you think..OP Tx

[M Gregg]

Just for interest,

Back panel completed....


Regards
M. Gregg

 

[Dimitris AR]

Nice work , keep going !!

 

[M Gregg]

Nice work , keep going !!

Thanks for the support,

I was going to put a metal plate support for the controls , however the shaft thread was to short so used a Dremel to reduce the cross section.

More to do..

Regards
M. Gregg

 

[M Gregg]

Just trying a few things for fun,

Whilst waiting for the Edcor OP Tx's...
I felt like I was building a model aeroplane for a while..
It will need to be strengthened but the concept seems OK.
If not there are lots of alternatives. (For a lid/top plate)


Regards
M. Gregg

 

[M Gregg]

Just some more done on the chassis/box,

The middle strut is held with silicone adhesive a bit of damping and no screws etc. However there is more to do

I have to sort out the venting and tidy it up a bit..its all just loose screwed together at the moment.


Regards
M. Gregg

 

[M Gregg]

More from the snail..

Rear venting in place, the top section will be held by the angled front and top section, then a couple of screws in the rear to hold it in place.
AKA standard in most metal OE enclosures.

I will alter the venting when I have a definite position for the tubes.
More work to do on the front.

Regards
M. Gregg

 

[M Gregg]

Tung oil finish and chassis glued etc.
I can start the build now.
Some supports to go in still waiting for Edcor OP Tx's.

Shield to make and fit across the rear of the volume control.

Regards
M. Gregg

 

[M Gregg]

Edcor,

Good news! You order has been shipped.



working on the mains and power Tx...Fitting MOV and NTC inrush suppressor.

Regards
M. Gregg

 

[M Gregg]

Just a bit more..

Mains wiring in, NTC and MOV fitted.
Volume pot, selector and mains switch mounted (shafts cut to size).
Faraday shield connected, rear panel bonded and star Earthing in place.

..more to do.

Regards
M. Gregg

 

[M Gregg]

yet more.

Selector wiring completed for the selector SW and back panel, Resistor feed for LED indicators so they all glow in the dark selected position is brighter.
Cruse light fitted with hot glue diffuser.

A couple of bases arrived today B9A McMurdo.

More to do..

Regards
M. Gregg

 

[M Gregg]

Just thought,

I would scribble the circuit for the selector on a piece of paper its very basic.
Just a few LEDs, relays and resistors. The 5K's could be altered to give more brightness, however you can only see the glow in a dark room + the selected input at standard brightness. (Just for fun)

I think the cruise lights make good on indicators. It seems to stand out without being intrusive. NB NOT BLUE (They are so uncouth)
If you don't use some hot glue to diffuse the LED you get a horrible bright spot.

Regards
M. Gregg

 

[M Gregg]

Yet more to do..

Tube caps fitted.
Small turret tag board made.

Regards
M. Gregg

 

[M Gregg]

Still waiting for the OP Tx's,

Input cable made using Teflon / silver and input board connected to the volume control.

Choke mounted and wired.
Screen made from EMI shield tape and aluminium.

Regards
M. Gregg

 

[M Gregg]

OP Tx's arrived.



Regards
M. Gregg

 

[M Gregg]

After a lot of thought,

I made a cradle for the tube rectifier for horizontal mounting pins 2-4 vertical plus a slight twist puts the plates side by side.
If I'm honest it was a PITA..
The thought of a couple of diodes drifted through my mind on more than one occasion but it would defeat what I'm trying to do.

Op Tx mounting holes drilled so I'm starting the speaker wiring.

Regards
M. Gregg

 

[M Gregg]

Temporary set back,

The Hammond Mains TX is faulty.

Yes the first time I have had a power Tx fail straight out of the box.<<ever!!!!I have fitted quite a few over the years.
Doesn't inspire confidence does it? (Hammond)<<first ever Hammond Mains Tx I have used!

I had powered the B+(HT) and it was working great, 5V and the HT all good.

So I thought I will just test the 6.3V. Nothing???????

Green-CT-Green. Green CT 3.15v other Green to CT 3.15v???? not possible Green to green 0V. Someone having a laugh here? The only way that could be, would be both green wires on the same end of the winding.

return to sender<<<
Replacement promised!

Regards
M. Gregg

 

[el156]

Temporary set back,

The Hammond Mains TX is faulty.

Yes the first time I have had a power Tx fail straight out of the box.<<ever!!!!I have fitted quite a few over the years.
Doesn't inspire confidence does it? (Hammond)<<first ever Hammond Mains Tx I have used!

I had powered the B+(HT) and it was working great, 5V and the HT all good.

So I thought I will just test the 6.3V. Nothing???????

Green-CT-Green. Green CT 3.15v other Green to CT 3.15v???? not possible Green to green 0V. Someone having a laugh here? The only way that could be, would be both green wires on the same end of the winding.

return to sender<<<
Replacement promised!

Regards
M. Gregg

Maybe it is a Hammond made in china ! They dont even tested it...

 

[M Gregg]

Maybe it is a Hammond made in china ! They dont even tested it...

It has made in Canada on it.
I am told they are supposed to clip a computer test rig to it and test resistances and loading, then a flash test and full load.

Well the full load test should show a 5A 6.3V winding with 0V.

I just have to wait again. It gives me time to play with a few things.


Regards
M. Gregg

 

[M Gregg]

While waiting for the power Tx,

Here is the voltage doubler board (control)
The RH84 module pentode driver. (trying to keep it small).
Kimber Kap coupling (Small size)
And screening/venting.

Still lots to do!

Regards
M. Gregg

 

[M Gregg]

Well update on Hammond,

Hammond aren't interested in one off Transformers, so The vendor is replacing it anyway!
ie it would seem Hammond won't replace the item. I reported the fault after 21 days.
Build time is an issue for testing.

NB if you use Hammond make sure you test it within 21days and keep all packaging.

Regards
M. Gregg