Lissen/Ever Ready 5214

[Mike Watterson]

It's the same radio.

Actually I remember I had a lot of trouble with the similar Model "A". It was the wavechange switch, which though 3 way rather than 2 way, does the band switching in a similar fashion.

If you look at the RF and LO parts and the LW, you'll see that on MW, the LW section of the LO coil is shorted out and the LW RF coil and trimmer is shorted out. Thus any contact resistance on those two contacts will detune the MW, affecting the HF more than LF.

Check the switches. Clean them. Meter them, even disconnect them and discharge a 10,000 uF cap charged to 10V to 30V through the closed LW contacts if all else fails. Also the LO has the series padder which can do odd things.

So don't assume the coils or variable cap is wrong, double check that the switch is really really two sets of shorts on LW!

[Amie]

Hi Mike.

Thanks so much for taking the time.

Yes this is the same set that Peter has mentioned on VRRR for me

I've read through your very thorough posts! Looking closer at the chassis I think I can see where the open rivets, (like eyelets), were spread. Some of the wires to the valve holders are connected into a solder toggle, then via a short wire to the tag, it suggests that you're correct about the modifications.

The tuning capacitor seems the correct value as does the LW coil, the MW coil reads 180uH. However 1370KHz ish, is the against the stop maximum on MW, at the moment

The sets were built to tune up to 180 metres ?

The LO trimmer is screwed right out, but it is checked as running at @ 1820KHz, IF is correctly aligned.

I'm thinking....
1.   Ultimately MW loop needs a redo....
2.   I need to find out why LO is running low.

I will start with your suggestions of checking around the LO switching....

I may use dads Taylor SIG gen for alignment, its calibration is very accurate, and its period compatible !

We are luck enough to be able to receive RTE on longwave here, with a reasonable signal, we like a lot of the programming, and its good that they have decided to continue for the time being, (mum is second generation ex pat).

I have two other ER radios, a case less late. K chassis, and a sky leader (later PCB version) transistor set.

Thanks very much for the help. I will keep you posted on how this progresses.

Amie

[Mike Watterson]

Don't think about the loops, they only affects sensitivity.

As a general principle either align MW & LW at these frequencies, or special marks on scale. Always check pointer / cursor is mechanically correct first. Never align at absolute ends of bands, especially the HF end as some caps increase slightly at fully open due to capacitance of mount, i.e. the minimum capacitance is often just before fully open.

Concentrate on the MW LO. Solder shorts across the switch contacts that close for LW as the symptom does sound like the LW LO coil switching isn't perfectly correct.
Referring to circuit I posted:

Part A:
1) T4 and LW secondary LO coil in series with T6 is shorted on MW. Solder a jumper across switch.
2) R4 and LW primary LO coil is shorted on MW. Switch resistance here will not so much detune. Only short switch here if step in one isn't enough.
3) T5 & LW RF coil are shorted on MW, don't worry about that. You can check later when LO is correct.
4) The LO trimmer on tuning cap T1 (furthest from drum) and T3 interact. T1 is HF end, adjust at about 1400 kHz (215 m)and T3 (likely in the IFT style can?) is the LF end, adjust on 600 kHz (500m). Repeat.
5) Remove the shorts. If the HF end shifts at all, then the switches are not Zero Ohms, especially the one in (1). Clean switch till no frequency shift on MW.
6) NOW trim the T2 (RF) for max gain at about 1400 kHz (215 m). Solder a short across the LW coil or the switch contact. Use as little signal as possible so AGC is at max gain (0V, goes negative. You can monitor DC volts on AGC line or AC volts at volume control. The MW loop coil is only "wrong" if no position changes the gain. THE LOOP NEVER AFFECTS TUNING, only gain. The number of turns sets gain at 600 kHz. It's unlikely to be wrong.
7) Remove the short on LW coil. If the signal level drops on 1400 kHz (215 m), then the switch isn't Zero Ohms on MW, clean it.

Only do Part B, LW, if the LO tuning on MW is correct at 600 kHz and 1400 kHz
1) The three switches are open on LW. T6 sets the LF end, about 170 kHz (1750m). The T4 sets the HF end, typically 252 kHz is a good choice unless it's the rarer set that tunes to over 300 kHz. These interact. So repeat. Do not worry about LW coil or T5, those only affect gain, not tuning. Do not adjust T1, T2 or T3, though they all affect LW as they are to set up MW. The T6 and T4 may not set band limits correctly if Part A isn't properly done.
2) Adjust T5 at about 252 kHz on weak signal generator or RTE1. If the LW loop is wrong it only affects the gain, never tuning. If T5 has no effect on gain, re-check MW and T1 at about 1400 kHz. Only consider the LW loop aerial being wrong if all the TUNING is correct, but reception is totally rubbish.

I do get the main UK MW stations here on the 1939 Lissen from dusk and the R4 LW all day. Tuning accuracy is reasonable and the trimmers on the main tuning cap look "normal". See where Limerick City is on a map. I'm 10km further west. The 1945-1946 Model A also correctly tunes but is a lot quieter.

[Mike Watterson]

The K and T are very similar. I surmise that it's based on the J, which wasn't an Ever Ready design apart from the package. The Sky Queen is essentially a D*96 125mA version of the K. There are cosmetically at least three versions of the K. Only minor circuit changes.
The T had many changes including incompatible 50mA series valves and the very last version is essentially the Sky Queen with 25mA valves. The Sky Prince replaced the last version of the T and is really the same chassis.
I think the K, T, Queen etc chassis design was Ever Ready's best MW/LW battery model and the longest in production chassis, with variations. Model K to Sky Lord. The Sky Lord seems to have still been retailed in 1961, though the Sky Captain was the last valve model. Early model T sets had a brass button to switch on scale illumination.

The C is poorly laid out compared to the 5214 / Model A or the later K/T/Queen/Prince etc.

I've a fair few more Ever Ready/Lissen than I've uploaded to the Radiomuseum. I've been writing rather than radioing.

[Amie]

Thanks again Mike!

I've taken a screen shot of your post and if I have a chance tomorrow I will go through your suggestions.
I'm now confident that even if not original, the capacitor is fit for service. I am aware that the signal loops have nothing to do with tuning. However on my set the MW one has been 'got at" and the wood frame is cracked/warped.

I will only attack that loop when I've got the LO sorted....

Long wave performance isn't too bad, BBC R4 is good, (maybe slightly displaced toward HF end) RTE reception readable.

Amie.

[Amie]

Part A:
1) T4 and LW secondary LO coil in series with T6 is shorted on MW. Solder a jumper across switch.
2) R4 and LW primary LO coil is shorted on MW. Switch resistance here will not so much detune. Only short switch here if step in one isn't enough

Actually, I tried your suggested process, and the LO HF end shifted up fifty KHz or so, the switch contacts looked quite black and dry so I gave them a clean with CTC and some vas to stop them oxidising again

Also the LO has the series padder which can do odd things

Bingo! I snipped one lead and measured C it was showing high. I set the oscillator trimmer to mid value, (about 30pf) then replaced the capacitor with a black cap ceramic the correct value. The Local oscillator can tune so I'm now able to line it up with the dial. Next is full alignment, Job for another day!

Top advice Mike.

Thanks,
Amie.

[Amie]

After receiving a couple of PM's its seems I wasn't clear what capacitor I had to replace....

As my set was fitted with an alternative tuning capacitor, it also had the capacitor marked C23 on Mikes diagram in an earlier post, its the Padder in parallel with trimmer C15, (I call the series tuning capacitors 'trackers'). the diagram in the trader doesn't show this part but does mention it in the text. For some reason it had gone high in value such that it couldn't be trimmed with C15, it was originally a silver mica component.

Thanks.
Amie.

[Mike Watterson]

Very unusual for silver mica to change and I can't imagine how they can go high.
The faulty ones on USA pre-1945 sets are usually a different construction and have HT across them. Usually they are a across coils or in series between a grid and coil so don't have ht across them. I wondered which capacitor you meant.

[Kalee20]

I'd say the same, too - don't think I've ever had a mica capacitor fail. Not completely unknown, but rare!

Maybe moisture got in, between the mica crystal-layer structure?

Anyway, whatever terminology is used, it was faulty, and it's now history!

[Amie]

No it's not Peter!!

Started to try to do a tracking alignment with the shabby MW aerial. The set was very unhappy with the repair showing signs of being unstable, breaking into oscillation unless there was a strong received signal.

I dug up the capacitor that I removed last, (looks like two thin oblongs of paxolin sandwiched together with rivets at either end, there were others similar in the set), and tested it again, it again read way high, 95pF should be 20....

It has no markings except a blue paint spot.

One end of the capacitor was connected to the tag on the under chassis side of the oscillator gang with a wire leading to the oscillator coil. The other side was connected to #1 and 2 tags on the octal socket of V2, (the metalizing/internal screen? Pin [1] ).

NB. The valve in V2 position in this set is a short 1N5GT that has no external metalizing.

I shorted pin 1 to pin 7 (filament -) so that the 20pF capacitor and V2 screen are now at signal ground.

The set is now well behaved and tracks up quite reasonably too....

As Mike suggested that this set had an octal conversion I wonder if the capacitor was misplaced then, or, if the set has always been crippled, and that the capacitor didn't go faulty it is plain just the wrong one fitted in the first place ? If it had been connected correctly, the radio couldn't have worked at all.

Hopefully it is now history!

Amie.