Rogers Ravensbourne FM tuner. Circuit diagram.

[North hill]

I have now recapped two Rogers Ravensbourne FM tuners mark 2 from 1973, both have a wooden case. I am looking for a circuit diagram of the model.

Thanks.

[Big jim]

Hi hope this helps and

[Trevor]

I have been looking for this schematic As I have one of these tuners many thanks
Trev

[Jon_G4MDC]

Is the signal meter bulb correct in the one with a red knob? Looking a bit over-run.

[North hill]

i have changed the bulbs for LEDs the output is high efficiency running at about 15ma giving the mains transformer more headroom as a lot of the power is from the E10 panel bulbs i did put a mains filter on the mains lead. the led looks bright in the photo !

[North hill]

hi thanks for the diagram for the Rogers fet tuner there are no values but its a good start i will print it out for good reference thanks for sending the file.

[Valvepower]

Hello,

I have the Circuit with component values and Installation/operation instructions for the Ravensbourne Series II FM tuner.

I can scan them and pop them on the forum in the next day or two.

Regards
Terry

[Trevor]

That would be great
Trev

[Valvepower]

Hello,

Here we go the Ravensbourne tuner manual.

Regards
Terry

[North hill]

One of the Rogers RAVENSBOURNE FM tuners has transistors in the PSU as well as an LM1310 Multiplex decoder there must be at least three versions of the Rogers tuners with passive and active power regulation depending on the version

[Radio Wrangler]

Note that the early version with the discrete transistor stereo decoder takes its outputs straight from the switch/matrix circuit to the output connectors without any buffering, so it's likely to be influenced by the input impedance of whatever amplifier it is used with. Also, there is no significant filtering of multiplex artefacts which could beat with a tape recorder's bias signal.

David

[Valvepower]

Hello,

I’ve taken some pictures of the inside of the tuner that came with the earlier scanned instructions… This differs to the circuit in the instructions.

I feel it has the discrete decoder, however it has an IC based IF and discriminator (SN76660). There is a two-stage ceramic filter feeding the IC based discriminator.

There is a small unidentified PCB on the underside - maybe birdy filter as it feeds the decoder?

The front end is a D&W module.

Another variant!

Regards
Terry

[North hill]

Originally Posted by North hill

One of the Rogers RAVENSBOURNE FM tuners has transistors in the PSU as well as an LM1310 Multiplex decoder there must be at least three versions of the Rogers tuners with passive and active power regulation depending on the version

the pictures are not the rogers tuner but as follows
1 stereofetic LEAK P.S.U. board new caps
2 Stereofetik LEAK I.F Board
3 Leak 2300 tuner FM board section with non polar 10uf caps all new

sorry about the confusion to everyone

[North hill]

Thanks for the photos i notice transistors my FM decoder in both the Ravensbournes i have the board has an LM1310 multiplex decoder IC i will post some photos at some point
thanks again the pictures are nice and sharp

[Valvepower]

Thanks for the update. Don’t worry these things happen.

…I must admit I had an inkling I had seen those circuit boards elsewhere, especially the Stereofetic…

Going back to David's comments regards MPX artefacts, the Leak Stereofetic uses a MPX filter and output buffer.

Terry.

[North hill]

Some more pictures of the Rogers tuners all two note one power supply PCB has transistors reminding me of the leak stereofetic power supply PCB also in my tuners both have am mc1310 stereo decoder and an output buffer stage.

[North hill]

Here is a good photo of the RAVENSBOURNE FM tuner stereo FM multiplex decoder PCB with buffer and MC1310 IC

[Valvepower]

Hello,

Thanks for the photos.

Interesting view of the decoder using the MC1310 IC. This IC became one of the de facto decoder IC’s in the halcyon days of the FM tuner.

I did also note the use of a Toko filter on the output of the decoder to filter out MPX artefacts.

Regards
Terry.

[North hill]

Yes the decoder works well thanks I did have to adjust the pot next to the i.c. on one tuner to get the stereo light and left right to work and the new red led uses very little power

[North hill]

Can anyone tell me the screws that hold the wood case to the chassis. I need to replace them that would be very much appreciated
Thanks