iturnknobs

Haufe BV107(09107) wiring for 7:1 in KM84 circuit
« on: February 10, 2019, 12:06:59 PM »
So, I am trying to  install this trafo into a KM84 circuit. I have tested primary tied together in series at 1.4Kohms. Each side of the secondary tests at 32 ohms. In order to have a 7:1 ratio I need to configure the secondary side to come up with 200 ohms as shown in the schematic from Haufe. I can come up with 32R(one side), 64R(both sides in series) or 16R(both sides in parallel). No matter what I do, I can't seem to come up with the "magical" 200R. Does anyone have any insight?


PRR

Re: Haufe BV107(09107) wiring for 7:1 in KM84 circuit
« Reply #1 on: February 10, 2019, 01:39:10 PM »
DC resistance is NOT audio impedance.

iturnknobs

Re: Haufe BV107(09107) wiring for 7:1 in KM84 circuit
« Reply #2 on: February 10, 2019, 06:01:05 PM »
DC resistance is NOT audio impedance.
Is this a clue as to how to wire/connect it? Should I just connect the yellow/green leads together, having white and blue connect to XLR pins 2/3? I'm going to try this which should work with the lowest output configuration... Ithink.

Sredna

Re: Haufe BV107(09107) wiring for 7:1 in KM84 circuit
« Reply #3 on: February 10, 2019, 09:35:02 PM »
Quote
Should I just connect the yellow/green leads together, having white and blue connect to XLR pins 2/3?

Yes.
The white lead of the secondary to pin 2, blue to pin 3.
Hmm... in which direction do the electrons actually go?

PRR

Re: Haufe BV107(09107) wiring for 7:1 in KM84 circuit
« Reply #4 on: February 10, 2019, 11:54:13 PM »
> white lead of the secondary to pin 2, blue to pin 3.

AND strap green-yellow.

That is if you want "nominal 200 Ohms".

If you really want " lowest output configuration", use the connections for "50".

iturnknobs

Re: Haufe BV107(09107) wiring for 7:1 in KM84 circuit
« Reply #5 on: February 16, 2019, 10:22:49 AM »
White to white(on primary side).
Green to Yellow(on secondary side).

white lead of the secondary to pin 2, blue to pin 3.

I have tested this wiring and it seems to be correct in this circuit.



Winetree

Re: Haufe BV107(09107) wiring for 7:1 in KM84 circuit
« Reply #6 on: February 19, 2019, 07:19:24 PM »
Red and Black wires?

iturnknobs

Re: Haufe BV107(09107) wiring for 7:1 in KM84 circuit
« Reply #7 on: February 20, 2019, 01:13:08 PM »
I personally wired red to red and black to grn on the Banzai PCB. Before replying, I did some homework, "transposing" the Cinemag CM-5722 schematic to the Haufe BV107 schematic and I suspect I may have wired mine incorrectly. I think that it could be wrong as far as polarity is concerned, but both mics definitely pass signal and sound alike and rather good. Maybe someone else can comment about correct polarity wiring.


 

Related Topics

  Subject / Started by Replies Last post
2 Replies
2039 Views
Last post July 16, 2004, 11:45:16 AM
by dukasound
11 Replies
3156 Views
Last post September 29, 2004, 12:20:31 PM
by
26 Replies
9409 Views
Last post July 18, 2011, 01:09:14 PM
by Insomniaclown
76 Replies
7745 Views
Last post February 23, 2019, 07:14:56 AM
by TillM