Windows freeware DWG/DXF editor & JPG or PDF-2-DWG/DWX conversion

Q1: What's a good freeware PDF (or JPG) to DWG or DXF conversion program?
Q2: What's a good freeware DWG (or DXF) CAD editing program?

I'm in need of a simple Windows DWG editor and a PDF-2-DWG conversion
because I have a simple CAD drawing in DWG & another in PDF I wish to
slightly modify.

Googling found this newsgroup had these discussions but they're all old:
06/12/2008 Simple CAD-type prog to edit DXF files, by Snapafun
04/08/2006 PDF to DWG or DXF Converter, by Thomas Friebe
10/24/2003 Freeware converting DWG/DXF into PDF, by Bernd Schmitt
10/02/2003 DXF Files, by H-Man
02/16/2003 DXF or DWG Viewer for Pocket PC, by NoSpam
08/17/2000 Autocad dwg and/or dxf viewer, by Dwayne

I have one DWG file and one PDF CAD drawing file I would like to edit.

Nowadays (2012), what freeware CAD drawing editor is recommended?

Googling, I found the following, but I know nothing about these.
Do you?

1. DiggFreeware "Free Open Source 2D CAD Software (DXF Viewer & Editor)"
2. CNET DXF Editor from "CAD-KAS"
3. TuCows "2D Viewer Editor: DWG DXF PLT TIFF CGM 8.0"
4. AnyCAD Free Version 1.4 (www.anycad.net/tag/dxf)
5. SolidWorks eDrawings Viewer (solidworks.com - might be just a viewer)

For the PDF to DWG converter, googling found the following.

1. CAD Monkey (blog.cad-monkey.net) using Inkscape
2. Ehow.com How to convert PDF to DXF With Freeware, using Aide PDF to DXF
Converter
3. Online free PDF2DXF converter www.pdftodxf.com
4. FreeSharewareCenter.com PDF to DXF Converter (20 free trialware)
5. anydwg.com/pdf-to-dxf.html Any PDF ot DXF Converter (30 free trialware)

But, before I go any route above, may I ask for updated information?

Q1: What's a good freeware PDF (or JPG) to DWG or DXF conversion program?
Q2: What's a good freeware DWG (or DXF) CAD editing program?

A screenshot of the CAD drawing that needs editing is here:
http://www2.picturepush.com/photo/a/11733040/img/11733040.jpg

I basically need to change the number of the squares on each side.
What Windows freeware would you recommend for that purpose?

 

Here's another screenshot showing what I'm trying to do in Windows.
http://www1.picturepush.com/photo/a/11733104/img/11733104.jpg

My first task is to edit the number of squares.
My second task is to convert the results to 3D rotation.
My starting point is DWG and PDF.

My goal is:
1. Convert PDF to DWG (or to DXF or to JPG, as needed for step 2).
2. Edit DWG (or DXF, depending on the output from step 1).
3. Convert the 2D DWG to 3D (so rotated CAD drawings result).

 

DraftSight by the Solidworks people.

 

Thanks for that wonderful suggestion!

DraftSight seems to be by Dassault:
http://www.3ds.com/products/draftsight/overview/

I downloaded it onto 32-bit WinXP and 64-bit Windows 7 and even without
registering it (yet), it loaded my DWG file easily. The download page
suggests it works on Mac & Linux too - so it looks like it fits the bill
of being a general purpose freeware DWG editor for the individual user.

The user interface is daunting, and it looks very powerful.
I was able to select a diagram and rotate it and save it so now I'll look
for a tutorial because this freeware CAD program is POWERFUL!

As you mentioned in the other post, it doesn't have depth, so I'm not
sure HOW I get things to 3D - but for the purpose of freeware editing of
a DWG file, this DraftSight program almost certainly will work for me!

 

The DraftSight interface is about as basic as any CAD interface is going to
get. I know what you mean though, if you don't have a lot of CAD
experience, just knowing what the different terms mean is a leap. I am by
no means a CAD user, but occasionally need a markup/viewing/printing tool.

 

You explained it perfectly.

The fact you say that the DraftSight interface is as basic as it gets
is great to know - because the main COST in freeware is the learning
curve of the various programs.

The entire PROCESS is to find the best one to start with.
That's the key!

If we choose the best freeware to start with, the learning curve is
worth it.

The worst situation is when we choose a lousy freeware program that
doesn't do the job. Then the cost is the sheer EFFORT involved in
determining the best freeware for the application (learning each one in
turn).

So, just knowing that it doesn't get simpler than Draft Sight tells me
that it's the way to go. At the moment, I've installed it on Windows XP,
Windows 7, and I've failed on two different Linux versions due to a
need for a shared object module that does not come with the RPM.

 

Just an FYI, Google has a sketching program that does 3D and is really
simple. I'm not sure what file formats is supported, but it would be worth
a look. For the most part, anything you learn in CAD you can leverage to
another product. Most CAD packages are designed by developers who at one
time all used AutoCAD. Most, therefore, use the same knowledge gained from
that.