Hi all Brian here I posted a bit of an intro in the other section
Firstly I'm very new to this but very keen to learn
.Im trying to repair a radio am I allowed to ask for advice here on what would case a problem I have ?

Thanks in advance
Brian

G'day Brian,

Ask away mate. This is what the place is for. There's quite a few people here who should be able to answer the questions you may have.

As well as describing the fault symptom(s), it will help greatly if you can specify the make and model of the radio.

If that is not known, and assuming it's a valve radio, then let us know the valve types in it (such as 6X4, 6X5GT, etc)

Failing that, some good in focus photos can be sent to Admin for posting here. Use Contact Administrator in the top menu.

Hi Guys and thanks for your welcome
First up I'm a novice in this but keen to learn and enjoying it. I repaired a couple of radios in that Ive replaced all of the caps including electrolytics, but trouble shooting faults is the big learning curve and I'm trying to learn how to read a schematic

Now the valve radio I'm working on is a Courier EC with the following valves

6K8GT 6K7 6B8 6F6 and an 80 The 6K7 and the 6K8GT have been tested ( not by me ) at 100%
Ive replaced all the caps being careful and did one at a time taking photos and sketches . I powered it up using a dim bulb tester which came on dimmed briefly and then slowly came up again. The problem is when powered on there is a bit of volume which dies away but if I hold the coated wire that connects what I call the tuning gang to the 6K8GT I get more volume, take my finger off nothing.I attached a wire to the tuning gang like an aerial and got the same effect as holding the wire

I hope thats not to much of a ramble
Regards
Brian

I know that this is no help in the current restoration.
But I am a firm believer in appraising the repair firstly by visual inspection, repairing/replacing any immediate obvious problem.
Then diagnosing and replacing any components which are stopping the unit from running.
Then in the interests of reliability, performance and safety replacing “all the caps”.
These sort of repairs have been my full time profession since the 1960’s..
At this stage of your current restoration, maybe a check of the tolerance of the resistors.
Should not take to long to do, but one end of the resistors need to be disconnected.
Will have a look for schematic, so as to help further.
JJ

Hi Powell,

I'm wondering about the antenna coupling transformer/coil. An inspection around the terminals and a continuity test of the windings may be a good start.

This seems to be the radio in question:

https://www.vintageradio.co.nz/model/golden_knight/ec

Includes schematic.

Thanks for that I have a picture of the schematic how do I post it
regards
Brian

You email pictures to Brad, look in his profile for the address.

Thanks found it and done

Thanks guys for all your replies. As I said and I will be straight up I dont yet understand what you guys are talking about yet so I will go with the transformer coil and try and figure that out.
Ive yet to test a resistor as I dont know yet how to read the colour codes
Thanks again
Regards
Brian

Just to muddy the waters I tried it again and the volume comes in high pitched waves , surges

Just found the schematic,
One resistor that would be very suspect, but may not fix your problem.
Is the 1/4 Meg marked on the circuit, which is 250K ohms going to the anode of the 6B8 (pin 3).
JJ

Just rereading your last post Powell.
It could well be that replacing “all the caps” with you current repairing knowledge may be a problem.
Some caps are critical in value, especially in the RF and IF sections.
The possibility of a wrong type or value throughout the radio would be high.
And replacing some would require a Realignment.
Need to carefully recheck your work, and also take a high resolution image of the under chassis, and post to Brad.
JJ

I think I have found it bear with me here, its red in colour with a yellow dot in the middle and green at one end. ?

Hi JJ
Thanks for that. I am confident that I have replaced the caps correctly as I wrote down the value of the cap and made a sketch of where it went I did all the old paper wax ones first and I understand about not using caps of a lower voltage rating.
I then replaced the eletrolytic caps making sure they were of the same value and voltage and polarity. This model had no canned capacitors on top of the chassis so made it a little easier
More than happy to be proved wrong if I have done it wrong and understand it may need to be realigned
I will see if I can post some pics of the underneath of the chassis I might try and do it in sections
Regards
Brian