Overlap Blocking Filter Pass 21-30
Product Code: PROOBF1A
- Overlap blocking filter Ch.21-30
- Used for blocking unwanted signals
- F-Type
- 1 input 1 output
Product Description
Overlap Blocking Filter Pass 21-30
A range of UHF band-pass filters from Proception, intended for blocking unwanted reception of transmissions from an adjacent region.
The introduction of high-power digital transmissions has led to problems with some receivers selecting multiplexes from out-of-area transmitters, leaving confused viewers watching the wrong regional services, or even listening to the wrong language!
Although this problem should be solved in the longer term by receiver developments, the use of band-pass filters can provide a quick, simple and cost effective solution, saving installers frequent call-backs.
Other Applications:
The entire range offers excellent cut-off below 470MHz and will help with problems from TETRA, telemetry and 70cm amateur band transmissions. Above channel 62 all versions will help solve GSM mobile phone interference problems, while the A and B models will additionally help suppress the forthcoming LTE (4G) signals.
Features:
- Optimised pass-bands cover most UK requirements in just four versions.
- Good out-of band rejection helps block TETRA and GSM, also LTE (4G), depending on model.
- F type connectors for good screening factor, helping prevent leakage around the filter.
- Good 75O match throughout the pass-band.
- DC blocked, no damage if inadvertently line-powered (24VDC max).
- Optional weatherproof outdoor housing available.
- Equipotential bonding terminal.
Technical Information:
| Product Code | Channels | Freq. | Lower | Upper1 | Insertion loss2 | Stopband Rejection3 | Conn. |
PROOBF1A | 21 - 30 | 470 - 550MHz | DC - 438MHz | 578 - 1600MHz | <3dB | >30dB | F |
PROOBF1B | 39 - 52 | 614 - 726MHz | DC - 578MHz | 762 - 1600MHz | <3dB | >30dB | F |
PROOBF1C | 48 - 62 | 686 - 806MHz | DC - 650MHz | 920 - 1600MHz | <3dB | >27dB | F |
PROOBF1E | 39 - 62 | 614 - 806MHz | DC - 562MHz | 920 - 1600MHz | <3dB | >27dB | F |
PROMHDCASE-S | Case for external installations | ||||||
1. Specified stop-band rejection is typically maintained to above 2GHz (but is not guaranteed above 1.6GHz).
2. Insertion loss may increase slightly at the pass-band edges, but will not exceed 4dB.
3. Typical stop-band rejection is around 35 to 40dB except close to the band edges.
Technical Specification
IEC or F Type
F-Type
Width
20mm
Depth
48mm
Height
80mm
Weight
0.04kg
Frequently Asked Questions
03/10/2025
01/10/2025
Delivered on-time without hitch.
25/09/2025
Excellent
23/09/2025
All good
14/09/2025
Spot on with everything needed good
Google Company Reviews
05/12/2025
Initially wrong products were picked and despatched. Replacements sent as soon as I made contact. Eventually good service
02/12/2025
Had to ring to see why I hadn't received my order, was told one item was out of stock, said they didn't know when they would receive the item but that same day it was sent to the courier, then still took another four days before I received my package,very poor packaging,hard to get into, one pole badly scratched and the other has a sticker on it that I cannot remove.
28/11/2025
Excellent, fast service and the aerial pole arrived in 100% condition.
22/11/2025
04/11/2025
item not received after a number of days. Reported by landline to Blake Head Office this morning.. Request replacement at no expense to myself. Please advise. Thanks. Anthony Ernest.

Exactly what I needed and delivered when said great team