[BUILD] CAPI FC526~500 Series~FET Limiter Kit~Official Support Thread

[Unit7]

Unlike Tony I feel lost without sorting sheets 

 

[Unit7]

I did that and was able to get one unit perfect and the other almost, because the RV8 hit the bottom and I settled for 2.489V with GR off and 2.235V with GR on. The meter behaves, but Jeff would you say that is close enough, or is there something funky about the RV8 hitting the bottom?

I think that is a little funky. There should be plenty of room on both trimmers to cal the meter in perfectly.

The issue with one of my units was probably because my old solder station was ready for retirement. Got a new really nice Weller today and reflowed most of the joints on the main board and both units are now operational! Thanks Jeff!

 

[jsteiger]

I did that and was able to get one unit perfect and the other almost, because the RV8 hit the bottom and I settled for 2.489V with GR off and 2.235V with GR on. The meter behaves, but Jeff would you say that is close enough, or is there something funky about the RV8 hitting the bottom?

I think that is a little funky. There should be plenty of room on both trimmers to cal the meter in perfectly.

The issue with one of my units was probably because my old solder station was ready for retirement. Got a new really nice Weller today and reflowed most of the joints on the main board and both units are now operational! Thanks Jeff!

Great news Paul! Thanks for the update 

 

[Kevinkmny]

Hi guys....

I was doing so great...made it all the way thru the build until the LEDs...

Soldered one side then removed the meter pcb to solder the other side...now I can't get the face plate back on to the front with the LEDs aligned properly and have snapped one of the LEDs in the process...

Any helpful tips?

Thanks in advance!

 

[jsteiger]

Hi guys....

I was doing so great...made it all the way thru the build until the LEDs...

Soldered one side then removed the meter pcb to solder the other side...now I can't get the face plate back on to the front with the LEDs aligned properly and have snapped one of the LEDs in the process...

Any helpful tips?

Thanks in advance!

The faceplate should be in place before inserting the meter PCB.

 

[Kevinkmny]

Seems so obvious now that you mention it

Thanks Jeff!

 

[jsteiger]

What LED's do you need to replace? Send me an email and I'll hook you up jsteiger1965 at yahoo

 

[Kevinkmny]

Thanks Jeff, I'll e-mail you...

I may have met my match with this meter pcb...I just can't get it seated..

I wonder if the best solution isn't to remove the existing LEDs and try again...

Not sure how to prevent the certain movement of the LEDs when you remove the PCM to solder the other side....

 

[jsteiger]

I wonder if the best solution isn't to remove the existing LEDs and try again...

Yes either that or look for the one or two that are holding things up and straighten them.

Not sure how to prevent the certain movement of the LEDs when you remove the PCM to solder the other side....

I have never had trouble with this. The LED leads are very stiff so I have never had them move. I am always pretty careful with them too.

 

[Kevinkmny]

Success! Now to move on to calibration and testing!

 

[Kevinkmny]

Well this isn't starting off well...

257 ohms at all 3 op amp V+
179 ohms at all 3 op amp V-

Any ideas?

 

[jsteiger]

What are the other opamp V DCR measurements? Basically we are looking for a direct short. I have never had one this low myself but it could be possible. I would try and make sure none of the 33µF caps have their pads shorted. If this all looks clear, I would power it up with no DOA's installed and make sure the PSU is stable and that you have expected +/- voltages at all of the opamp sockets.

 

[furn1979]

Hi Jeff...

Just finishing my first of two 526's. Things went pretty smooth!

I believe 4 x 22p capacitors are missing from the 4 Opamp Adapter Kits. Can I swap them with caps of other value?

Thanks!

 

[jsteiger]

I believe 4 x 22p capacitors are missing from the 4 Opamp Adapter Kits. Can I swap them with caps of other value?

No they are not required for the LME49710's. I only added the spot on the PCB in case someone uses a 5534.

 

[the new frenchy]

Hi everybody,

I build to kit of FC526, one is ok, and calibrate; and the other has a problem.

my problem :

for TP1 I find 0.02volts with the Bypass toggle up to BYP and 0.002volts with the Bypass toggle down to ACT ....  :'(

I change the opamp and retake some solder between the receiver and the output transfo...

I need some help!!!
thanks for yours!!!

Jérôme

 

[the new frenchy]

 

[the new frenchy]

 

[the new frenchy]

 

[jsteiger]

Sounds to me like the relays are not activating. Check the components around them especially the location of the zener diodes as well as the 3904 transistor.

 

[jsteiger]

I also see many questionable looking solder joints. It could be one or more colder solder joints. What temp is your iron set at? I run just below 800˚F. Maybe a good cleanup and reflow would help.