Being a VHF tube is no bar (ECC88, for example, has been used in many successful designs). But the ECC85 doesn't bring anything special to the audio table. An ECC81, for example, will have similar mu and gm, but has better linearity in voltage amplifiers and is readily available (still in production).
With some effort, one could use the ECC85 in a reasonably good preamp, but why bother?
With some effort, one could use the ECC85 in a reasonably good preamp, but why bother?
---
It makes an even more better Cascode stage !
Yep, nothing further to add to ! From time to time I'm restoring old radios and the ECC85 is essential in most FM Tuners. Please use ECC81, it's basically the same valve ! The same counts for ECC84, ECC804, ECC807 etc. which are rare and needed as spares for existing commercial products. There are soooo many other double triodes you could use, please do so.
It makes an even more better Cascode stage !
Yep, nothing further to add to ! From time to time I'm restoring old radios and the ECC85 is essential in most FM Tuners. Please use ECC81, it's basically the same valve ! The same counts for ECC84, ECC804, ECC807 etc. which are rare and needed as spares for existing commercial products. There are soooo many other double triodes you could use, please do so.
Hello...
Can I use alternatives to ecc85 in phillips capella 673?
I have 6n1p sometimes it is mentioned as possible alternatives, and sometimes not.
Please help.
There is also this mention, but it is on german, as far i can understand , it is possible to use them as replacement.
http://www.radiomuseum.org/tubes/tube_6n1p.html
Can I use alternatives to ecc85 in phillips capella 673?
I have 6n1p sometimes it is mentioned as possible alternatives, and sometimes not.
Please help.
There is also this mention, but it is on german, as far i can understand , it is possible to use them as replacement.
http://www.radiomuseum.org/tubes/tube_6n1p.html
Last edited:
I tried once to replace ECC85 with 6n1p and it worked quite well.
The sensitivity dropped a bit, but the local oscillator was exactly at the same frequency
I did not want to fine tune the tuner circuits, but obviously this could improve the lost sensitivity.
You can try if it works on Philips Capella or not.
The sensitivity dropped a bit, but the local oscillator was exactly at the same frequency
I did not want to fine tune the tuner circuits, but obviously this could improve the lost sensitivity.
You can try if it works on Philips Capella or not.
To change ECC85 to 6N3P or 5670 in FM-tuner is bad idea.
All together 5 pins of 9 must be rewired.
In such circuits working at 100 MHz, the lay-out is quite critical and lead lengths has a big effect to overal operation.
I would not even think about this modification.
In case of audio frequency this would be a simple task.
All together 5 pins of 9 must be rewired.
In such circuits working at 100 MHz, the lay-out is quite critical and lead lengths has a big effect to overal operation.
I would not even think about this modification.
In case of audio frequency this would be a simple task.
The basic reason is that the ECC85 is a variable transconductance tube. This means its transconductance is dependent of the grid bias, and this behavior is used for AGC circuit in VHF/UHF tuners. For audio we need (relatively) constant transconductance for minimizing the distortion of the stage.
6N3P is the most typical tube used in Soviet radios as FM-tuner and works well.
But because it has different pin-out, it is not a good replacement for ECC85.
If I had no ECC85 to replace, I would try 6N1P and make the re-adjustment of the first IF-transformer, as suggested here: 6n1p, Tube 6n1p; Röhre 6n1p ID18834, Double Triode
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.