help me please

[Aerodyne]

I'm a little puzzled. If you mean you intend to replace the resistor marked with 'dr', fair enough as that's a necessary part of the HT line filtering but the other resistor, unmarked and across the DC side of the rectified HT, is bridging the HT and so it must be a high resistance. Frankly I don't see the need for it other than it being some sort of bleed for the HT upon switch-off and perhaps acting as a peak voltage limiter on switch-on - a thermistor perhaps - until the valves begin drawing current. It seems to me to be a quirky design altogether and it also looks designed for 230V AC mains.
Or am I completely wrong in my assumptions?
Tony

[pwdrive]

Maybe DR is a choke, valve bias is taken from the bottom of the heater chain at the junction with the tapped resistor, not sure what that thing is across the HT it has the same type of symbol as part of the output transformer?

[EDIT: Across the HT = Loudspeaker Field Coil?]

Lawrence.

[boiss]

Please forgive me if I'm wrong but I reckon it was made for 220 V too, The chain of valves Lamps and VDRs would indicate it running on about 230/240V Dc, I can't remember much about selenium rectifiers but they often had heatsink fins and were made up of many series elements. I think they used to drop around 40V too, so this starts to put it in the right ball court. The VDRs won't work properly until a bit of juice is put through them. Check all the valve filaments with a DVM. Check that the bulbs are the correct type. You can remove a valve, calculate the value of a substitute resistor for all the valves in series (Normal running) and put the resistor in place of all the valves. Check the voltage across the resistor, if it is the same as the valves normal total running voltage (check datasheet, someone mentioned 117V I think), remove the resistor refit the valve and off you go............. Fitting another large resistor in series as suggested may confuse things due to the VDRs and cold valve and bulb filament resistances.. A good sign would be the dial lamp brightness. BTW DR in German could mean drossel meaning inductor or coil, usually the Loudspeaker field coil was in the series path as a smoothing choke (DR here). The unmarked L with a core across the HT is a bit weird??
Hope this helps

[pwdrive]

I would also say it's for 220v operation, I'm sure that's a field coil across the HT (see link below)

http://www.trioda.com/shop/index.php?page=schematic&schematicid=550

Lawrence.

[boiss]

Lawrence, On that diagram it's stated as "Field" too, With a value of 13K R ? it's a likely candidate to go O/C as well.
Mike

[pwdrive]

Yes that's why I posted the diagram for a similar model as it is clearly marked field (feld), where as it is not so on the OP's diagram, yes definately a candidate for O/C, not sure what the working HT is on the OP's radio is, peak can be worked out from 220v RMS less say 25 volts for the selenium rectifier drop which would put the HT at around 270 v at the reservior (unloaded)

Lawrence.

[Aerodyne]

As I said about DR - its part of the HT filtering but I missed the fact that the German symbol looks like a resistor! If it IS field, that means the LS is an energised type. Field windings are notorious for failure, as most of us know to our cost. Perhaps we need to wait and see what results from Hawk's tests, i.e. does the set work now?
Tony

[pwdrive]

Yeah Euro diagrams, they sure draw them funny, it took me several goes to work out the diagram for the small Indesit B/W portable TV when that first came out, anyone remember them?

Lawrence.

[Old Sparky]

Is/was this radio designed to run from 110-120vac by any chance? Reading the above posts, and looking at both circuit diagrams I'm nor sure, but remembering that some continental countiries used to use 110-120v mains made me wonder. What are the heater voltages of the valves used?

[Aerodyne]

The valve heater chain comes to around 117v , as Alan has mentioned earlier (actually I added them to 115 but knowing me and numbers, that's probably wrong) but together with the chain of VDRs and the lamps, the total appears to be in the 230V region. That is of course on the assumption that (a) I know what I'm talking about and (b) I've correctly recognised the symbols despite the German nomenclature.

Tony