UKW-Koffersuper LD452AB

The "ferrite rod" and coils was missing, but central connection strip/saddle remains.
Looking at rear, there are 3 connections:
a) is both connected S21 and S22
b) is other end of S21
c) is other end of S22
Which of S21 and S22 is LW and which is MW?
From rear on the three connections, left to right, which is a, b and c?
What is total inductance of S21, it is in two parts?
What is total inductance of S22, it is in two parts?

Is the spacing of the two parts of S21 to adjust inductance? Similarly for S22?

I obtained 200mm ferrite rod and glued on a 33mm section so the rod is 233mm and fits on bracket. It may of course not be same permability.

In the absence of other information I will try a few very old  MW and LW transistor radio coils on the large ferrite rod.

Dear Colleagues,

I found this on the LD480 Annette page

Which side is LW and which side is MW?

Inductances?

Thanks,

Michael

Dear Michael,

please have a look at the documentation for LX452AB which should be the 'same' model for the dutch market I didn't check too deeply, but it looks good.

There is a complete service documentation in Dutch here (PDF deep link).

Hope that helps,
Mark

I had to replace the missing AM cord and found the RMorg drawing didn't work. After watch the drum wind / unwind I figured the correct winding on tuning cap drum.

Anyhow, page 9 of that link has the correct lacing for the AM cord.

Incidently I found that a red plastic covered steel paper clip "opened out" made an excellent replacement AM dial pointer/needle.

The S21, S21', S22, S22' are only part number. But now I have the value of AM RF tuning capacitor (9 to 498) and thus can calculate the coils by taking LF end of LW and MW band.

I will wind 30 turns on ferrite and measure the inductance and thus have the Permability at a few MHz (the test frequency of my PIC based tester) and also measure it on a meter that uses kHz (it does 20H max).

Then I can put the permabitily into the coil winding program. I'll just make S21 = S21' and S22 = S22' as they look similar. Infinitly far apart the inductance will be double with two indentical coils in series. Up close forming a single coil the inductance is quadrupled as N squared would apply as if a single coil. So that is how S21 and S22 are adjusted to set LF end of band. The padding capacitors set HF end.

Thanks Mark.

Die "Ferritstab" und Spulen fehlte, aber zentrale Steckerleiste / Sattel bleibt.
Mit Blick auf Rückseite befinden sich 3 Anschlüsse:
a) ist sowohl verbunden S21 und S22
b) ist anderen Ende der S21
c) ist anderen Ende der S22
Welche der S21 und S22 ist LW und die MW?
Von hinten auf die drei Verbindungen, von links nach rechts, die a, b und c?
Was ist insgesamt Induktivität der S21, ist es in zwei Teile?
Was ist insgesamt Induktivität der S22, ist es in zwei Teile?

Ist der Abstand der beiden Teile der S21 bis Induktivität einstellen? Ähnliches gilt für S22?

Ich erhielt 200mm Ferritstab und verklebt auf einem 33mm Abschnitt so wird der Stab 233mm und passt auf Bügel. Es kann natürlich nicht gleichzeitig permability werden.

In Ermangelung anderer Informationen, die ich noch ein paar sehr alte MW-und LW-Transistor-Radio Spulen auf dem großen Ferritstab versuchen

Liebe Kolleginnen,

Ich fand diese auf dem LD480 Annette Seite

Welche Seite ist LW und MW, welche Seite?

Induktivitäten?

Danke,

Michael

Where exactly does the VHF aerial coax connect to on the Chassis? It's only connected to what used to be the telescopic aerials.

I presume my set is this set as the remaining part of valve layout label shows a DC90 in the first position instead of a DF97.

When you remove the Chassis from case there is a set of tags and a Resistor sized RF choke on the front of VHF tuning module. I presume this might be where it was pulled off?

I think it's clear where the coax cable goes. I will add a photo later if/when the radio is working!

Anyone working on the VHF section of this set will appreciate the information in DC90 as Additive Mixer article. Joe Sousa has added to the main article a good description of the alignment issues for Local Oscillator.

For those confused as to what a DEAC is (probably anyone not involved with restoring a German Portable, or not having used vintage Remote Control Aircraft) here is the Manufacturer page. It took me a while to find as a simple Google search suggests Varta (the actual owner though) not Deutsche Edison-Akkumulatoren-Company GMBH. The DEAC D2 would appear to be not much different in capacity (a little more than 2000mAH?) to a modern AA size NiMH, though it's much larger. In the 1970s an AA size NiCd from Sanyo was about 450mAH and NiMH in 2011 vary in capacity from 1800mAH to an optimistic 2800mAH. The capacity of a D size cell (similar size to Kofferradio DEAC?) varies from 2500mAH (likely an AA cell in a D box as it feels very light) to 10,000mAH in 2011. Capacity of NiMH C cells is commonly 3500mAH.

Are there dimensions anywhere and a scan of the battery case / card for the battery used?

The Ever Ready B117 (= Vidor L5515) is a 90V HT battery with the same snap on connectors, but I think a smaller size?

I want to make up an "actual size" pack using CR2032 coin cells rather than PP3 as they are only 9 cents each (in 100s inc postage, Euros). I used 6 stacks of 26 cells connected together via 6 x 1N4148 for a B126 (total cost under €16 for maybe 150hrs). For intermittant use shelf life can be 15 years and for continious use if you can get per stack current down to about 1mA you get nearly 150 to 200 hrs for a pack.

Cheap Zinc Carbon PP3 are olny about 8 to 16hrs good operation (usually 6 stacked rectangular cells) and good Alkaline now seem to use 6 x AAAA cells (600mAH or less, down to 200mAH maybe at 10mA), 20 to 50 hrs use depending on HT current (usually between 5mA and 15mA).

NiMH PP3 have several issues for HT application :

1) Charging many in series

2) Per pack is nominal 78 vs 90 if 6 cells per PP3

3) About 200mAH only

4) High self discharge. Unless "Eneloop" type, could be "flat" in a month.

5) Cell reverse charge on discharge.

Is this Pertrix 78 the size used?

Yes, this is the correct H.T. battery. I found an elder specimen from about the mid 1960s in my Philips LD452AB. Two more pictures are loaded to the battery's page.