![]() |
![]() |
![]() |
|
Vintage Radio (domestic) Domestic vintage radio (wireless) receivers only. |
![]() |
|
Thread Tools |
![]() |
#1 |
Pentode
Join Date: Nov 2018
Location: Burnley, Lancashire, UK.
Posts: 100
|
![]()
Had this little gram in stock for a few years now, when it arrived the record player worked fine but no radio, I have just pulled it out as a winter project, both electrically and cabinet restoration, upon firing it up very low audio on record player and some low interference on radio channel, its well worth restoring as it has FM channel, any ideas on a starting point would be very much appreciated Best regards Ron H.
|
![]() |
![]() |
#2 | |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 20,643
|
![]() Quote:
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
|
![]() |
![]() |
#3 |
Dekatron
Join Date: Oct 2003
Location: Southport Lancashire, UK.
Posts: 3,135
|
![]()
The generally accepted starting point is to get the audio amplifier section working properly then proceed "back" to the radio sections.
The record player problem may be with the cartridge. Crystal ones especially deteriorate with age.
__________________
Paul |
![]() |
![]() |
#4 |
Pentode
Join Date: Nov 2018
Location: Burnley, Lancashire, UK.
Posts: 100
|
![]()
Thanks for your replies guy's, on removing the chassis it has become apparent that a major component seems to be missing, there is a four hole socket between v4 and what looks like a condenser, looking at the underside one of the wires goes to the other condenser etc, I have the schematic CD 1 but unfortunately this is no help as there is no chassis above or below pictures that could confirm my suspicions, If anyone has an above and below chassis photo or can tell me where I can buy one it would be a great help, as of now I am stopped. Best regards Ron H.
|
![]() |
![]() |
#5 |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,166
|
![]()
Could you give us the model number and perhaps a picture of said capacitor.
|
![]() |
![]() |
#6 |
Pentode
Join Date: Nov 2018
Location: Burnley, Lancashire, UK.
Posts: 100
|
![]()
Hi there Michael thanks for your reply, the model is Invicta 60RG also known as model 38 I have schematic but nothing more
|
![]() |
![]() |
#7 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 20,643
|
![]()
Two of the connectors of that socket are wired directly to an adjacent valveholder. Can you tell us which valve and which pins please.
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
![]() |
![]() |
#8 |
Dekatron
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,450
|
![]()
Socket to connect to
a tuning indicator in a different model ? Lawrence. Last edited by ms660; 10th Oct 2022 at 1:11 pm. Reason: extra info |
![]() |
![]() |
#9 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 20,643
|
![]()
Given that the valve is probably V1 an ECC85 I'm thinking the wires go to pins 4 and 5 the heater. That fits in with pin 3 (k2) being earthed. Difficult to tell though as only part of the valveholder appears in the picture.
Perhaps a feed for dial lamp or LT supply to some external kit?
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
![]() |
![]() |
#10 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 20,643
|
![]()
I've also noticed that this is a six valve radio, but I can only see five valves. Is there on in a screen can or something?
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
![]() |
![]() |
#11 | |
Dekatron
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,450
|
![]() Quote:
Lawrence. |
|
![]() |
![]() |
#12 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 20,643
|
![]()
Yes I can just make out a black screening can there, so that makes the valve the socket is connected to V2.
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
![]() |
![]() |
#13 |
Pentode
Join Date: Nov 2018
Location: Burnley, Lancashire, UK.
Posts: 100
|
![]()
Thanks for your reply Graham, The valve is valve No2 on schematic Mullard ECH 81 pins 4&5, thank you Best regards Ron H.
|
![]() |
![]() |
#14 |
Dekatron
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,450
|
![]()
So far as I can make out the Pam 714 uses a similar chassis and has its tuning indicator connected via a 4 pin chassis socket and plug although in that one the position of the 4 pin socket and V2 are transposed to what's shown on the OP's chassis.
Lawrence. |
![]() |
![]() |
#15 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 20,643
|
![]()
Could be. A picture of the whole valveholder would clear things up.
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
![]() |
![]() |
#16 |
Dekatron
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,450
|
![]()
The bottom tag of the 4 pin socket in the under chassis photo is connected to the AGC line which would be needed as a feed to a tuning indicators grid, you can see the 1 Meg AGC feed resistor that's connected between that tag and pin 2 (g1) of the ECH81.
Lawrence. |
![]() |
![]() |
#17 |
Pentode
Join Date: Nov 2018
Location: Burnley, Lancashire, UK.
Posts: 100
|
![]()
Better picture of V2 from below and picture of valve layout showing all 6 valves as requested, best regards Ron H.
|
![]() |
![]() |
#18 |
Dekatron
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,450
|
![]()
Definitely a socket for a tuning indicator connection.
Lawrence. |
![]() |
![]() |
#19 |
Pentode
Join Date: Nov 2018
Location: Burnley, Lancashire, UK.
Posts: 100
|
![]()
Thank you Lawrence, so can I take it that this will not affect this model ? Best regards Ron H.
|
![]() |
![]() |
#20 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 20,643
|
![]()
The OP now knows that nothing need be plugged into the four pin socket. He has a circuit diagram with voltages, so getting the set to work shouldn't be a problem.
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
![]() |