|
Vintage Radio (domestic) Domestic vintage radio (wireless) receivers only. |
|
Thread Tools |
11th Sep 2020, 8:04 am | #1 |
Heptode
Join Date: Sep 2010
Location: Hythe, Hampshire, UK.
Posts: 632
|
Help - Grundig 8055/W/3D
I'm currently repairing a Grundig 8055/W/3D with an outboard circuit which is a clearly a pre-amp with some equalisation. The input states "Collaro Transcription Cartridge" and the output is connected to the normal PU input. My question is what is the Collaro cartridge mentioned (it's missing from the arm) I've never run across one of these.
Hoping someone can help |
11th Sep 2020, 12:10 pm | #2 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,340
|
Re: Help - Grundig 8055/W/3D
This is liable to be for the Collaro Studio "P" crystal cartridge (c.50mV) or the (even better) Collaro/Ronette TX88 cartridge. Both are rare, have wide frequency ranges and a relatively low output - hence the pre-amp add-on circuit.
__________________
Edward. |
11th Sep 2020, 3:20 pm | #3 |
Heptode
Join Date: Sep 2010
Location: Hythe, Hampshire, UK.
Posts: 632
|
Re: Help - Grundig 8055/W/3D
Thanks for the information Edward, that now makes sense. Looks like I'm going to have to install a ceramic pickup and skip the pre-amp if they are so rare.
|
24th Sep 2020, 3:19 pm | #4 |
Heptode
Join Date: Sep 2010
Location: Hythe, Hampshire, UK.
Posts: 632
|
Re: Help - Grundig 8055/W/3D
To keep the circuit original I used a Sontra CS25 stereo ceramic cartridge which has the following specification:
Output: 45 mV 1cm/s at 1000 Hz Frequency Response: 20Hz to 18 kHz Compliance: 6 x 10(-6) cm/dyne Tracking Force: 3 to 5 grams It sounds fantastic! |
25th Sep 2020, 9:46 am | #5 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,340
|
Re: Help - Grundig 8055/W/3D
No, you will still need to use that dedicated pre-amp section. Most "new" ceramic stereo cartridges have a far lower output than you might expect!
__________________
Edward. |
25th Sep 2020, 1:05 pm | #6 |
Heptode
Join Date: Sep 2010
Location: Hythe, Hampshire, UK.
Posts: 632
|
Re: Help - Grundig 8055/W/3D
It's not a 'modern' cartridge it's an original Sontra coupled to the pre-amp.
The output is exactly right when switching between Radio / PU - and as I said it sounds fantastic! |