Hello there.

How interesting.

I have another post in the General Discussion forum requesting the identity of a dial and what set it belonged to.

My chassis looked very similar to the one that is pictured including the same power transformer and the IFs.
The controls were the same, even the broadcast aerial coil was the same and mounted in the same position.
Same short wave coils and same chassis layout with the funny earthing tabs.
The dial layout was different though, the dial pointer rotated 180 degrees instead of slide rule style.

Mine used a 6A8G instead of the EK2G.

Could it have been the same manufacturer?

I have another post in the General Discussion forum requesting the identity of a dial and what set it belonged to.

That thread:

https://vintage-radio.com.au/default.asp?f=1&th=1007

Valve line-ups give us probably the best clue to possible manufacturer, especially in the case of bespoke sets where the chassis is often made by an undisclosed major radio specialist and the cabinets and dials can be tailored to the requirements of the seller -- such as a department store chain.

The Eclipse Monarch of 1940/41 had a lineup of 6A8G 6U7G 6B6G 6V6G 5Y3G, but so did about another 40 sets from a variety of manufacturers, spanning mantels and consoles.

That as said was superseded by EK32. The closest pin equivalent is 6A8 & 6J8 will work, (not necessarily the same) in each others socket

6A8 won't directly interchange with EK32. EK32 pin 1 must be grounded. cathode resistor will be around 500 Ohm for EK32.

But G2 is the big difference. 6A8, 6J8, 100V EK32 200V.

Pin 4 EK32 G3 +5 50V; 6A8 100V

6J8, EK32 ..... Valves not electrically the same, not interchangeable: Wiring will be modified.

Marc

Update,

It is now going but lead me a merry dance as the oscillator kept stopping & flicking the band change switch to SW & back to MW set it going again. Hunted & hunted around the band change switch proving nothing until again checking the Osc coil winding that has the HT through it suddenly went open circuit.

Dragged that out of the chassis as one can not see all 4 connections easily & there on the underside were 2 small green spots of corrosion. Touched one & a fine wire sprung up as did the other one when touched with the tweezers. Bugger!

Luckily the 2 bits of missing coil winding were right at the end so by sacrificing 2 turns of the Osc coil I then had a DC path through it once more. Back in the set things really sprang to life & I gave the IF section a quick check through with sig genny & all looked good.

Had to tweak the padder capacitor on the osc coil to drag the stations back from way down one end to about mid dial (no dial glass to accurately check but roughly right) & then tweaked up the aerial trimmer & it all looked good. BUT there is a "birdy" right on 6IX over here which sits at 1080kHz and nothing I do can get rid of that whistle does anyone have any pointers as to how to eliminate that most annoying whistle??

IF Transformers are different in that IF 1 has NO adjustable slug screws sticking out each end. It has 2 holes in the top can with what look like could be trimmer caps..one does move & has a BIG effect on signal output. The other looks similar but could well be stuck as does NOT want to move either direction. In between sits what looks like could be a lock nut assembly on a central shaft which could be a slug adjuster but has NO screwdriver slot in the top & is almost flush with the nut itself. IF 2 is the usual type IF with slug adjusters each end.

Any ideas on how to remove this "birdy"??

Lindsay

Any ideas on how to remove this "birdy"??

Rogue harmonic/s getting through filtering. Usual suspects are capacitors, bad solder joints, poor component placement (especially point to point wiring).

Have you recapped this set?

GTC, Yes totally recapped the thing & will go back rechecking values of the ones I have swapped over just in case I have left a "0" out of one somewhere & gotten a way out value installed. There are 2 paper caps I did not change as tested Ok with the 500V tester & showed no leakage unlike others that were totally shorted. These couple only have at max about 20V on them.

Is all a bit weird as after running for a few hours the whistle all but vanishes?

Lindsay

I've found that birdys and squirly noises often come from the audio output stage, strange as it seems. Usually caused by faulty negative feedback networks and associated tone control, or just by having a wire from the speaker being too close to the valve.

Sometimes just moving the output valve in its socket just a bit will clear it.

The other cause is a bit more logical, missing or disconnected shielding of the IF valve. Sometimes you see the 6U7G resplendent in its goat shield, but it isn't grounded.

Well...FOUND that "birdy" quite by accident when trying to lift the performance of the set from around 1000 Kz up to 1200kHz where 2 stations are that are coming in very weakly.
The "birdy" tone was coming in right on 1080 kHz & was being injected somehow via the earth lead as when I unplugged a small battery charger that is associated with a backup 240V supply for the house (big inverter, 48V battery bank plus 1500 Watts of solar) the tone disappeared.
Plugged the charger back in & it came back on 1080....Charger NOT switched on however & the only other thing there apart from inverter was the 40A solar controller. Switched off the solar array & no more birdy, switched the solar back on & as soon as the MPPT solar reg started to charge again there was the birdy...Whew so its NOT the set after all.

Now to work out just why the higher end of the MW band is so low in performance. The antenna trimmer makes no real improvement and there was a weird looking coil of fine wire hooked up via the band change switch that ended up across the oscillator coil wiring associated with the tuning gang. It broke off as I was trying to work out the band switch connections being made out of quite fine wire & was encapsulated in wax which when I melted off so I could chase the end of the broken wire and there was NOT a circuit through the thing...almost like some crude form of homemade capacitor but what it did exactly I have no idea as the set runs fine without it.Seems to anyhow.

Correct me if I have gotten this wrong but from memory one tweaks the trimmer cap on the tuning circuit to peak the high end of the band & the slug of the tuning coil. If NO slug then the padder capacitor does the similar job which is how this set it built..only a padder capacitor.
I have peaked both & still the top end of the MW band is very poor.

Any further hints to bring the sensitivity up a wee bit more as to hear either 1080 or 1206 stations one needs the volume control flat out.

The slug is for the low end, and the trimcap is for the high end.

The objective way to do the alignment is to do the IF stages first. Then go to the padder (where fitted) and adjust it (normally around 600kHz) then adjust the aerial trimmers (1500kHz). I normally do the high end of them on a weak station, antenna attached.

If the set does not have a ferrite antenna. Then an antenna needs to be fitted to get any form of reception. Keep the signal strength down & use a series cap if attaching to a signal grid. You only need about 50uV on the grid.

the only other thing there apart from inverter was the 40A solar controller

So, external RFI. Solar systems are right up there among the top generators of radio interference.

It should be fairly obvious to us all, that you can now make, use & import all that above, NBN boxes & faxes etc. and anything else that puts out masses of RFI & EMR with absolute impunity.