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 6BD7 VALVE
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 Return to top of page · Post #: 1 · Written at 10:33:57 AM on 21 December 2023.
Bowler's Gravatar
 Location: Bongaree, QLD
 Member since 26 October 2018
 Member #: 2308
 Postcount: 81

Hi All, wondering if any one had a replacement workaround for a 6BD7 VALVE. Bowler

Radio cabinet


 
 Return to top of page · Post #: 2 · Written at 6:57:33 PM on 21 December 2023.
DangerousDave's Gravatar
 Location: Toongabbie, VIC
 Member since 1 September 2020
 Member #: 2438
 Postcount: 131

Interestingly I have found an Astor BPJ with a 6AN7 in place of the 6BD7 that was working well with only what appeared to be the AGC that was compromised. When you look at the makeup of both valves it can be seen how it does work. I did end up putting a 6BD7 back in its place.


 
 Return to top of page · Post #: 3 · Written at 9:47:37 PM on 21 December 2023.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2039

6BD7 can be replaced by EBC80 or EBC81.

What radio is it for?


 
 Return to top of page · Post #: 4 · Written at 10:03:48 AM on 22 December 2023.
Bowler's Gravatar
 Location: Bongaree, QLD
 Member since 26 October 2018
 Member #: 2308
 Postcount: 81

Good Morning Robert, The radio I am working on is a Philips model 165. Valve lineup is as follows 6an7, 6bh5,6bd7,6m5, 6x4. Bowler


 
 Return to top of page · Post #: 5 · Written at 2:51:25 PM on 22 December 2023.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2039

Ah, those sets work pretty well given their unassuming appearance. Weak points:
- speaker transformer will often be found to be open circuit
-.the socket for the dial lamp is rather cheap and can misbehave.
- broken dial cord

You said 6X4 - they normally came with a 6V4, was that a typo?

I have a few examples of this radio, and also a green Fleetwood clone.

Was your 6BD7 missing? The main problem I find with the 6DB7 is it can get noisy. I would have thought that a replacement would be fairly easy to find considering how many radios used it.

If you can't find one you could temporarily convert the radio to a Model 164, which involves bypassing the 6BD7, and replacing the 6BH5 with a 6N8 with rewiring the socket.

An alternate solution would be to replace the 6BD7 with a 6N8, and rewire that socket to suit, not forgetting to add components for g2. And you get more volume as a bonus.


 
 Return to top of page · Post #: 6 · Written at 11:14:59 AM on 23 December 2023.
Bowler's Gravatar
 Location: Bongaree, QLD
 Member since 26 October 2018
 Member #: 2308
 Postcount: 81

Hi Robert, thanks for the information. Yes the 6X4 was a typo. Any idea where I might get a dial scale for this radio? bowler


 
 Return to top of page · Post #: 7 · Written at 1:04:04 PM on 23 December 2023.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2039

I have a spare case, not sure if it has a dial glass (could be plastic). I'll have a look next time I'm out that way next week.

Can you post a photo of your radio so we can make sure I'm thinking of the right radio?


 
 Return to top of page · Post #: 8 · Written at 4:46:27 PM on 28 December 2023.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7342

Photo uploaded.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 9 · Written at 8:53:49 AM on 29 December 2023.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2039

Thanks for the photo, it is the radio I was thinking of. Some, like that one had the chicken wire on the front, and some had cloth instead.

I notice it has a plastic dial included. It's hard to tell, but it looks a bit scratched? Anyway I found my radio and it also has the dial, with the original unique gold-coloured screws to hold it in.

At the bottom (inside) there's a small bracket to hold the dial lamp. It shines onto the edge of a flat plastic piece, designed to send the light evenly to the entire dial. There's also a metal piece there (can't remember what it did).


 
 Return to top of page · Post #: 10 · Written at 10:03:28 AM on 29 December 2023.
Bowler's Gravatar
 Location: Bongaree, QLD
 Member since 26 October 2018
 Member #: 2308
 Postcount: 81

Hi Robert, are you prepared to sell the dial glass or the whole case? bowler


 
 Return to top of page · Post #: 11 · Written at 3:17:17 PM on 29 December 2023.
Redxm's avatar
 Location: Tamworth, NSW
 Member since 6 April 2012
 Member #: 1126
 Postcount: 466

Bowler
email me your address, I have a 6BD7 I will send you. It has a good filament, unable to test further

Ben


 
 Return to top of page · Post #: 12 · Written at 8:46:33 PM on 12 January 2024.
BurntOutElectronics's Gravatar
 Location: Melbourne, VIC
 Member since 2 October 2019
 Member #: 2392
 Postcount: 271

What's the process for retrofitting a 6N8 to replace a 6BD7?


 
 Return to top of page · Post #: 13 · Written at 9:47:16 PM on 12 January 2024.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2405

Here are instructions to wire it as a triode.

1. Plug in the 6N8. Do not switch on yet.
2. Remove wire from Pin 6. Connect it to Pin 7 (remove ground connection from Pin 7 if present).
3. Connect Pin 6 and pin 9 to Pin 1.

Simple!

If you want more audio gain, wire it as a pentode - follow on instructions here:

4. Lift connection from Pin 1. (Leave the connection to Pin 6)
5. Connect Pin 1 to B+ with a 1 meg resistor.
6. Connect a 100nF cap from pin 1 to ground.
7. Remove Pin 9 connection to pin 6 and connect Pin 9 to ground.


 
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