[ICOM] Heil HMP

[Ken, WA2LBI]

I know this is crude but here is the diagram of my HMP mic preamp.  I just
finished it; I believe it is correct.  Use a fixed font like Courier.  I have
this in a plain text file that I can send as an attachment if desired.

                             Heil HMP Microphone Preamplifier


         Microphone socket (to mic)                    Icom mic plug (to radio)
                                        |------------------------o-----< Pin 2 
8V (green)
                                      1.0K                       |
                                        |                        |
                Ferrite bead            |       + 4.7µF Tantalum |
                |    .1µF        D------o-----||-----------------|--[]-< Pin 1 
Mic hi (white)
      Pin 1 >--[]-o---||---o---G (MPF102)                        |   |
                  |        |     S-----o-----||------o           |   Ferrite
bead
           .001uf =        |           |    +  4.7uf |           |
                  |        |           |    Tantalum |    .001uf =
                  |       2.2M        1.0K           |           |
                  |        |           |             |           |
         Pin 7 >--|________|___________|_____________|___________|------< Pin 7
Mic lo (shield)
                  |            Ground
         Pin 6 >--|


         Pin 5 >--------------------------------------------------------< Pin 5
PTT (red)

73,

Ken




Quoting Anders Janis SM4RNA <sm4rna at telia.com>:

> I have received several requests of the reflector to pass along a schmatic if
> I receive one. Seems that its a hard to find item.
>
> /Anders
>
>
> ----- Original Message -----
> From: "Randall M. Payne" <payner1 at earthlink.net>
> To: "ICOM Reflector" <icom at mailman.qth.net>
> Sent: Monday, September 05, 2005 9:38 PM
> Subject: Re: [ICOM] Heil HMP
>
>
> > If possible, I'd like a copy also
> > Thanks in advance.
> > 73,
> > Randy K4EZM
> >
> > Anders Janis SM4RNA wrote:
> > > Anyone that can send me a schematic of the discontinued Heil HMP mic
> preamplifier?
> > > /Anders