Hi all, I've been busy and finally getting back to this project. I'm struggling to know for sure if I'm reading this colour code correctly as I am finding different answers on various sites while googling for the correct information. Unfortunately there is no circuit diagram available to check with. Could any of you more experienced please let me know the correct way to read it ? I will send a picture of the resistor to the webmaster in a moment.

Those resistors use the Body - End - Band system. They read as follows:

Body: 1st number

End: 2nd number

Band: number of zeros following.

Example:

Brown = 1
Green = 5
Orange = 3 zeros

Hence, 15000 or 15k ohms.

These resistors have a 20% tolerance.

I think that chassis was made by Technico, who later became Pye.

Hi Ian, thanks for clearing that up for me. What wattage are these usually? I'm guessing I will be using higher wattage anyway to replicate physical size.

Photo uploaded to Post 46.

250K ohms - often used as the anode load resistor on the audio triode. A 220k or 270k will do fine as a replacement.

I would check that with an ohm meter There is no brown the paint has fallen off I have one with pretty much the some colour its marked 0.25 meg and is no longer in the radio as its 295.3K.

Thanks for your replies. That resistor comes off 6M5 output tube, plate pin 7 and goes to another which looks like same value but is larger and that resistor goes to pin 3 of the 6N8. There another different value resistor connected to the junction between the two resistors.

That 250 k resistor is a half watt.

The next size up is 1 watt.

The resistor in the picture measures at 300K. The other that I mentioned measure at 215K. I also mentioned another resistor off the same junction, it is blue orange blue green 65K? It measure at 100K.

That does not sound right. B+ Wires & resistances wandering off to other places will not be on the plate Pin 7 Only the speaker transformer should be on that with perhaps a capacitor.

Pin one perhaps, as that is grid 2 Screen; six & nine are dead pins. Check that you are reading it right? 6M5 is a nine pin most common in HMV. The others tended to use 6AQ5 7pin. Read clockwise from Gap base or wiring side.

I don't know the set or the circuit, but a high value resistor hooked to the output valve plate is seen occasionally.
It could be a plate-to-plate feedback loop to the previous valve?
Fred.

It sounds like a weird circuit as pin 3 of a horrid little 6N8 is its cathode. Very rare to see a cathode follower arrangement for feedback. Grid 2 is pin1 6N8. Pin one 6N8 & pin one 6M5 I can see linked to B+ and high value resistors cutting the power to a 6N8, as detector 1st AF.

It is a "bitsa":L Strange when its got bits of the era of AWA 563MA-Y that it uses 5Y3. Its using some Ducon (Cheney is Ducon) caps, the black mud's that crack & short are AWA (dump the lot). Transformer is Ferguson. Trimmers Philips, I suspect.

Whilst it is down and outright tedious, it may be a case of reverse engineer. I usually get the AutoCAD and draw the elements in their position (Gang, Xformers, Tube sockets) Then play join the dots, preferably with colour: From that layout diagram you get the circuit and pick out the mistakes.

I also thought this to be weird as I'm using a couple other circuits with the same valve line up as a reference. Strangely enough it actually works albeit for only a short period. The bias voltage just keeps increasing to way above from what I understand it should be. I posted that comment to see if the far more experienced had come across this before. I think someone has make this error at some time. I will now check out the circuit against what info I have to try and work it out.

One more question, is 5 volts on pin 3 of the 6M5 the sort of voltage I should be aiming for? I have noticed that on another circuit.

Thanks again for all your help here.

Sorry I made a mistake. Pin 6 of the 6N8 not pin 3 as I earlier typed. My apologies for the error.

Voltage on the control grid pin2 6M5 is governed by the cathode resistor and how hard they want to drive it it will be in the order of 140 to 170 Ohms and if things are right the voltage across Rk will be the grid voltage. Has it actually got a cathode resistor? That may have a bearing on why it grinds to a halt.

Pin 6 of 6N8 is its Anode that may if 1st AF, be fed by a single resistor, perhaps from pin one of 6M5 (screen). OR Two in series with a decoupling cap in the middle. From the anode there will be a capacitor to pin 2 of the 6M5.

https://frank.pocnet.net/sheets/084/6/6M5.pdf
https://frank.pocnet.net/sheets/201/6/6N8.pdf