Home Theater Forum and Systems banner

21 - 29 of 29 Posts

·
Registered
Joined
·
565 Posts
I've now had the B-1 for a month or so and it's awesome.

It quit running warm to hot after a few days. Perhaps burn in time.

I'm recommending its use for anyone who integrates home audio to pro audio amps for excellent bass control, much better than simply using the gains on the pro amps or the freq cutoff of the receiver.

Happy camper here.....:rofl2:
 

·
Registered
Joined
·
7,514 Posts
Discussion Starter #22
It has the 16V capacitors and what appears to be the same transformer. It's marked 12V on the output side. My DMM measures 16 VAC coming directly off the transformer on both the + and - sides.
The DMM is measuring the RMS value from the transformer (not peak).

To choose capacitors for that RMS AC voltage, it requires converting to peak and adding about 10% for line variations. This value would then be the minimum capacitor voltage allowed in the design.

So: 16 volts x 1.414 x 1.1 = ~ 24.8 volts WVDC capacitors required. (25 volt capacitors are the next standard size) :)

brucek
 

·
Registered
Joined
·
1,249 Posts
The DMM is measuring the RMS value from the transformer (not peak).

To choose capacitors for that RMS AC voltage, it requires converting to peak and adding about 10% for line variations. This value would then be the minimum capacitor voltage allowed in the design.

So: 16 volts x 1.414 x 1.1 = ~ 24.8 volts WVDC capacitors required. (25 volt capacitors are the next standard size) :)

brucek
Do you actually get variations in the line voltage of ten percent? :raped:
 

·
Registered
Joined
·
7,514 Posts
Discussion Starter #24
Do you actually get variations in the line voltage of ten percent?
Not likely, but this a design limit to determine the minimum size for a capacitor. Another rule of thumb in sizing capacitors is twice the RMS value of the secondary (which would 32 volts in this case). The next standard size would then be 35 volts. I think peak plus 10% is quite adequate in this case though. The spec is working and not surge (which they don't usually specify anymore), so 10% overspec should be fine.

The problem (as you know) with under spec'd capacitors is that they don't just fail, they explode. The dielectric (insulator) can only withstand so much voltage and then the DC will pass between the plates causing the capacitors electrolyte to heat up. This creates internal pressure that can cause the can to explode. Most capacitors have vents though (either plugs or stressed marks on the end of the can) to reduce the risk of an explosion. I've taken lots of dead equipment apart in my time that looked like a mouse was living in there, only to find it was a demolished capacitor.

There's next to nothing in that F-1 box that should get hot. If it's hot, check those filters to see if that's the source. If it is - shut it off....... :)

brucek
 

·
Registered
Joined
·
10 Posts
Hello, I am new to the forum and was wondering if someone could help me with some questions.
All answers are greatly appreciated.

I am attempting to modify my Reckhorn F-1 to get unity gain from the satellite output.
I modified the R3, R12 - change from 3.9K to 10.7K

The problem is that I am using a scythe kama amp with a TEC pre-amp and the volume is still a lot less with the Reckhorn in the chain that without the Reckhorn.

I am new to this modding game and would like to ask, if it is possible to get more than unity gain from the sat outputs? If so, what are the affects on clarity, humming etc.

Thanks alot and look forward your comments.
 

·
Registered
Joined
·
5 Posts
Hello,
I know this thread is old, but i want modify my Reckhorn F1 too.
Is it possible to get the exact values from the resistors and capacitors(which had been changed)?
Greetings Adrian
 

·
Premium Member
Joined
·
19,397 Posts

·
Super Moderator
Joined
·
5,869 Posts
You could also send an email to Reckhorn. I got the schematic for mine a few years ago when I had a A402. He might be able to help you with some direction if the OP doesn't remember.
 

·
Registered
Joined
·
1 Posts
Hi,

My first post.

I was wondering if somebody could post a part list for this Reckhorn F-1 modification?(and perhaps more pics)
I got those right cap values and did that but would also like to do the rest.

Thanks in advance.
 
21 - 29 of 29 Posts
Top