The MI-4045-A comes from a period when RCA was establishing many of the standards for professional audio:
Expansion of national radio networks
Development of standardized broadcast equipment
Early evolution of microphone design before widespread ribbon adoption
These early MI-series microphones laid the groundwork for the later, more widely recognized RCA ribbon models.
If you own or are contemplating purchasing one of these microphones for use or restoration this manual is INVALUABLE for that process. Each technical drawing has been painstakingly restored so the schematics are clear.
Why a Digitally Remastered Manual Is Valuable
Original RCA BK-series manuals from the late 1940s–1950s period are often:
Lightly printed on thin stock
Faded or yellowed
Difficult to read in schematic sections
Incomplete when found today
A professionally remastered edition provides:
Clear, high-resolution page restoration
Legible wiring diagrams and connection information
Accurate technical specifications
Preserved original layout and formatting
Reliable reference material for servicing and integration.
The time-consuming remastering process involves carefully scanning the original manual and spending hours processing each page to produce a manual that looks better-than-new. All photos are stripped out and processed separately. All tears, marks, stains, etc. are removed from the original manual, even printing defects were corrected. The text is brought back to original sharpness and detail, as are all of the illustrations.
We use heavy stock matte or premium glossy photo paper for the front and back covers, and heavy paper for the inside pages. The outside covers are protected by 10 mil thick, clear plastic sheets. It is then bound with plastic ring comb binding so the manual will open flat and be very durable.
We combine shipping to save you money. Our preferred method is USPS Priority Flat Rate Padded Envelope. Our international sales are handled through eBAY and they instruct us where to ship the merchandise for processing to your country. If you wish another method of shipping or want to make sure the shipping price is accurate, please contact us. Our standard policy will be to refund any excess shipping that eBay's calculator may charge over a modest handling fee for your entire purchase.
REVIEWS: "Absolutely gorgeous item." "Super Professional Work." "America Needs More Like You!":
Please see our store for other items you may want. We have produced:
Protective Covers: For both a desk stand and boom mic. Models 74, 77, 44 + Western Electric 639A/B
Manuals (digitally restored) ** see list below**
Supplements (remastered articles & info for the avid RCA fan)
Artwork - digitally restored advertisements AND a unique commissioned 44/77 microphone print
T-Shirts - unique graphic artist design onto high quality 100% cotton material that lasts for years
Other logo'd special items.
RCAmic.com Digitally Remastered Manuals: BK-1A; BK-4A; BK-5A; BK-5B; BK-6B; BK-11 (BOTH VERSIONS); SK-46; SK-50; PB-144; AEROPRESSURE; VARACOUSTIC (6204, 6204); 1933 JR VELOCITY; 44-A; 44-B; 44BX-(-B, -D); 44BX-G, 44BX-(-H, -J, -K, -L); 50A; 74-A JR VELOCITY; 74-B 1937 jr VELOCITY) ; 77-B1; 77-D; 77-DX; 88A. We also have digitally remastered the manual for the Western Electric / Altec the 618 and a separate manual for the 639A/639B.