You could actually use the cabinet for your first valve amplfier...
I recommend staining it with walnut.
The speaker you have looks to be 8 inch or 10 inch, go and buy a brand new manufacture old-design Jensen guitar speaker to suit the cabinet and......
Start on a simple 6V6 design or go for a 6GW8 or 6BM8 push-pull amplifier, even better, go for an EL84 design.
Then build it to the cabinet and...
Stick in an LCD display and a VIA EPIA motherboard, setup a suitable SMPS power supply, you certianly have the space for it..then walla!
A vintage multimedia centre with DVD capability /AND/ the old sound!
Then buy a heap of old episodes of programs on DVD and you've got yourself an 'old-world' cabinet.
I recommend staining it with walnut.
The speaker you have looks to be 8 inch or 10 inch, go and buy a brand new manufacture old-design Jensen guitar speaker to suit the cabinet and......
Start on a simple 6V6 design or go for a 6GW8 or 6BM8 push-pull amplifier, even better, go for an EL84 design.
Then build it to the cabinet and...
Stick in an LCD display and a VIA EPIA motherboard, setup a suitable SMPS power supply, you certianly have the space for it..then walla!
A vintage multimedia centre with DVD capability /AND/ the old sound!
Then buy a heap of old episodes of programs on DVD and you've got yourself an 'old-world' cabinet.
lol!
$900 later.... I really not sure.... like i said, theoritically, this amp did work... I will think about it, probably take me a while to restore the cabinent anyway... if i were to upgrade it, i may use an old pentium 100. lol. stuff it full of mp3s n put a lcd screen or even a old monitor in there with a few fans,.. im not sure...
aaniel
$900 later.... I really not sure.... like i said, theoritically, this amp did work... I will think about it, probably take me a while to restore the cabinent anyway... if i were to upgrade it, i may use an old pentium 100. lol. stuff it full of mp3s n put a lcd screen or even a old monitor in there with a few fans,.. im not sure...
aaniel
i did actually read that very simple diy valve amp on here, sounded interesting, but in know the transformers would cost an arm n a leg. Im not really interested in spending heaps of money.. this was one of those, killing time projects.. use parts lying around.. i think the speaker is 12inches in it.. 1200ohms? maybe...
Daniel
Daniel
The speaker itself wouldn't be 1200 ohms, in these early sets they had the output transformer on the speaker itself, so when you read the speaker's ohmage you're actually reading the primary-side of the output transformers ohmage, the actual winding that matches with the output valve, in this case a 6V6...
The output transformer secondary from the coil on the speaker chassis, goes to the speaker windings...
You could always gut the receiver section of the chassis out and still use the power transformer and re-build the amplifier circuit from scratch using the power transformer, the only major thing other than that would be a new output transformer, where you can put as you please, in the area where the receiver section is, or with the speaker..
Hammond output transformers don't cost the earth! not for what you want, a nice 6V6 or 6GW8.
http://www.evatco.com.au/transformers.htm
Especially for such a common amplifier.
Cheers!
The output transformer secondary from the coil on the speaker chassis, goes to the speaker windings...
You could always gut the receiver section of the chassis out and still use the power transformer and re-build the amplifier circuit from scratch using the power transformer, the only major thing other than that would be a new output transformer, where you can put as you please, in the area where the receiver section is, or with the speaker..
Hammond output transformers don't cost the earth! not for what you want, a nice 6V6 or 6GW8.
http://www.evatco.com.au/transformers.htm
Especially for such a common amplifier.
Cheers!
Hi Daniel,
Glad your P2200 worked out. I restore old radios as well. My humble suggestion ... Don't do anything you can't recover from to the chassis and speaker. Refinish the cabinet as you see fit. Give the radio a shot to restore it.
You may find the caps are not working anymore, you can put modern ones inside the old can, preserving the look. What you want to do is power up the unit (speaker in circuit, it's part of the power supply) on a variac. Don't bring it up to full voltage. Try say 50 - 60% while watching the current. If you don't get smoke or sparks, and the current is okay, let the unit sit there for a while. Watch it while it's on. At this point you can make some measurements while at reduced voltage and heater current.
You could run the heaters off an external 6.3V transformer with a high enough current rating, disconnecting the original heater winding. You can then increase the AC slowly and watch for proper operation. This way you have some time if things start to go wrong.
I've worked one many radio's, some just for laughs.
-Chris
Glad your P2200 worked out. I restore old radios as well. My humble suggestion ... Don't do anything you can't recover from to the chassis and speaker. Refinish the cabinet as you see fit. Give the radio a shot to restore it.
You may find the caps are not working anymore, you can put modern ones inside the old can, preserving the look. What you want to do is power up the unit (speaker in circuit, it's part of the power supply) on a variac. Don't bring it up to full voltage. Try say 50 - 60% while watching the current. If you don't get smoke or sparks, and the current is okay, let the unit sit there for a while. Watch it while it's on. At this point you can make some measurements while at reduced voltage and heater current.
You could run the heaters off an external 6.3V transformer with a high enough current rating, disconnecting the original heater winding. You can then increase the AC slowly and watch for proper operation. This way you have some time if things start to go wrong.
I've worked one many radio's, some just for laughs.
-Chris
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.