PL 700 solder point pulled away from control board

[Wheel-right]

Ed, is there a way to determine the year, age of the amp I have by S.N. ? Is that info over at the "https://www.phaselinearhistory.stereomanuals.com/700seriesamp.htm" site ? I must be missing it if so.

Maybe this page might help, Ed's post #5 at the bottom of the page.
https://forums.phxaudiotape.com/threads/what-was-the-build-year-of-my-pl-400.8312/#post-244682

 

[VSAT88]

Here is mine. I looked but for a second or so. Thanks for that have not de ciphered it, yet...

 

[oldphaser]

Here is mine. I looked but for a second or so. Thanks for that have not de ciphered it, yet... View attachment 38727

If you have the original output transistors or power supply capacitors they will have 4 digit date codes on them that will give you a relative idea when the amplifier was built. Usually a few months after the transistor or capacitor indicates.

 

[WOPL Sniffer]

Yep this board could have been among the very 1st lots made for the PL 700's .

View attachment 38726

No luck, mine had a PL-20 in it. Never seen one in this good of condition. This 700B must have been babied. When I opened it up, it had some delay mechanism in it. It was tied in to the speaker jacks/Zoebel...... You could set it for 1 second or up to like 10 hours... I'll have to post a pic of it.... Friggin gadgets....

 

[VSAT88]

If you have the original output transistors or power supply capacitors they will have 4 digit date codes on them that will give you a relative idea when the amplifier was built. Usually a few months after the transistor or capacitor indicates.

Thanks Ed. When I dive back in I would like to check that out of pure curiosity.

 

[VSAT88]

No luck, mine had a PL-20 in it. Never seen one in this good of condition. This 700B must have been babied. When I opened it up, it had some delay mechanism in it. It was tied in to the speaker jacks/Zoebel...... You could set it for 1 second or up to like 10 hours... I'll have to post a pic of it.... Friggin gadgets....

Hell yeah, great score. I would like to check a look at the delay mechanism thing. Never heard of such...

 

[J!m]

My Counterpoint amps have an on-delay circuit. It allows the main caps to charge fully before passing audio.

 

[mlucitt]

My Counterpoint amps have an on-delay circuit. It allows the main caps to charge fully before passing audio.

How big are your Counterpoint main caps? This site is interesting:
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capchg.html

Capacitors will reach 63% of the charge voltage in one time constant and maximum (99%) charge voltage in 5 time constants, hence the formula: t=5xRxC where t=time in Seconds, R=resistance in Ohms, and C=capacitance in Farads.

I'm not sure what the effective resistance (R) would be in the 100VDC main capacitor circuit of our PL amps? Maybe .1 Ohm? If that is true, a 15,000uF (C) PL700 cap will reach maximum charge in 5 x 1 x .0015 or .0075 seconds after the DC voltage is applied.

 

[J!m]

There are four per amp; each about the size of a beer can.