Published on 10/13/2026
A buyer emails: "Need 50 SMA cables, 1 m, please quote." The supplier replies with five questions. Male or female on each end? RG316 or RG174? Straight or right-angle? Any VSWR limit? Tested how? A week passes before the quote is even possible, and then the parts that arrive have an RP-SMA on one end because nobody said otherwise.
A complete request for quote (RFQ) removes that loop. It lets the supplier price the exact part, build it right the first time and test it against the right limits. This guide lists everything worth stating, explains the ones that cause the most mistakes, and ends with a template you can copy.
For choosing cable and connector in the first place, see our RF coaxial cable selection guide. For what the test report should show, see our article on cable assembly test reports.
On This Page
| Item | What to state | Why it matters |
|---|---|---|
| Connector A and B | Series, gender, polarity, straight or right angle, body style (for example SMA male straight, RP-SMA female bulkhead) | The most common ordering error is gender or polarity |
| Cable type | RG316, RG174, RG58, RG142, semi-rigid size, or low-loss type | Sets loss, flexibility, temperature, power |
| Length and tolerance | Overall length, how it is measured (connector end to connector end), and tolerance, for example plus or minus 5 mm | Measuring reference changes length by 10 to 30 mm |
| Frequency range | Operating band in MHz or GHz | Drives connector and cable choice and test range |
| Electrical limits | Maximum VSWR or minimum return loss, maximum insertion loss at stated frequencies | Defines pass or fail |
| Quantity and schedule | Prototype count, production volume, delivery dates | Affects pricing and where it is built |
| Marking | Label text, serial numbers, color bands, heat shrink color | Avoids rework |
| Strain relief | Boot, heat shrink, overmold or none | Durability |
| Environment | Temperature, outdoor or indoor, flex or static, chemicals, vibration | Selects jacket and sealing |
| Test and documentation | VNA sweep range, report format, certificate of conformance | Defines the deliverable |
| Packaging and compliance | Bagging, labeling, RoHS or REACH needs, country of origin | Customs and receiving |
Item 01
Connector gender and polarity
Say which has a pin and which has a socket. An SMA male has a center pin and a female thread. An RP-SMA reverses the center contact. Attach a photo or a datasheet link if unsure.
Item 02
Length reference
State whether length is overall including connectors or cable only. For right-angle connectors, state whether to measure to the centerline or the end face.
Item 03
Frequency and limits
A cable used at 2.4 GHz does not need the same limits as one used at 26 GHz. Give the band and the worst-case limit, not just a general quality level.
Item 04
Cable construction
Flexible, semi-flexible or semi-rigid and the jacket type. For bending and routing see our bend radius article.
Item 05
Test scope
Tell us which parameters you want swept and over what range. We sweep every assembly for VSWR and insertion loss before shipping.
Send us your specification
Fill the template and our engineers will respond with a quote.
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What should I include in a cable assembly RFQ?
Connectors on both ends, cable type, length with tolerance, frequency range, electrical limits, quantity, marking, environment, test requirements and delivery date.
How do I specify an SMA cable assembly?
State the connector on each end (SMA or RP-SMA, male or female, straight or right-angle), the cable type, the overall length with tolerance, and the frequency range.
What is the tolerance on cable length?
For general use, plus or minus 5 mm to 10 mm is common. Tighter tolerances such as plus or minus 1 mm are available but must be requested and priced.
Do I need a drawing for a custom cable assembly?
Not for standard connectors and cables, but a drawing or photo helps for unusual connectors, marking, or routing.
How are cable assemblies tested?
Typically by VNA sweep for VSWR or return loss and insertion loss, plus continuity. At SigmaRF every assembly is VNA-swept before shipment.
How fast can I get a quote?
A complete RFQ lets us quote quickly. Missing details are the main cause of delay.
What is the difference between RP-SMA and SMA?
RP-SMA reverses the center contact: the plug has a socket and the jack has a pin, with the same thread. They will not mate with standard SMA.
Can SigmaRF build to my drawing?
Yes. Send the drawing or the completed template and our engineers will confirm the build.
Good RFQs list connectors, cable, length, frequency, limits, quantity, marking, environment and test requirements. The template above takes five minutes and saves days.
SigmaRF builds standard and custom coaxial assemblies from 100 MHz to 40 GHz at our India (Vadodara) volume facility and USA (Cleveland area) precision facility. Each assembly is VNA-swept for VSWR and insertion loss before shipment, and lead times can be as short as 2 days.
Ready to send your RFQ?
Paste the template into a message to our engineers or request a quote.
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