Ham Radio Homebrew Informations: Re: [HamBrewers] 144 - 146 Mhz (2M) Rx thoughts [2 Attachments]

Tuesday, May 31, 2011

Re: [HamBrewers] 144 - 146 Mhz (2M) Rx thoughts [2 Attachments]

[Attachment(s) from Raj included below]

Some data sheets attached.

At 01-06-2011, you wrote:

Hi! Raj,

MC13135 and its earlier variant MC3362 is still available at Delhi if anyone interested. Lately I stopped going in for complete discreet ones cause found it easier modify surplus items, but that barely scrathes the itch of a totaly homebrewed project.

73's

Rahul VU3WJM

--- On Wed, 1/6/11, Raj <vu2zap@gmail.com> wrote:

From: Raj <vu2zap@gmail.com>

Subject: [HamBrewers] 144 - 146 Mhz (2M) Rx thoughts

To: HamBrewers@yahoogroups.com

Date: Wednesday, 1 June, 2011, 9:08 AM

For two meters I would suggest the obvious "kiss" mode.

I will leave out the PLL/DDS part out of discussion for now. We have others who can suggest.

One chip of the series MC3357, 3359 and so forth.. will do the major task of conversion, limiting & detection! These devices are designed for cordless phones and are for NBFM.

Some thoughts:

You have the front end built in the later chips. Others require the first mixer e.g. 3357

Some chips require a discriminator coil/cap and others resonator.

10.7 or 21.4 Mhz & first IF 455 second IF (first IF depends on your junk box xtals)

Audio stage:

No more LM386 please. It took many years to get out of the clutches of LM380!

Now I suggest the TDA2822 stereo amp in push pull mode. I found this chip very

stable and took a lot of abuse. I got a great sound in my RX project. Cheap!

Hi,

I am also interested in this project.

I am also requesting VU2ZAP to give his thought in this regard.

with 73's

de VU2GAQ

Kumar Gautam

Ex- VU3KGL

--

Raj, VU2ZAP

Bangalore, India.